diff --git a/.codeclimate.yml b/.codeclimate.yml
index 975bbe566c8..009a4859a06 100644
--- a/.codeclimate.yml
+++ b/.codeclimate.yml
@@ -6,7 +6,6 @@ languages:
 
 exclude_paths:
  - "app/assets/javascripts/defer/*"
- - "app/assets/javascripts/discourse/lib/Markdown.Editor.js"
  - "app/assets/javascripts/ember-addons/*"
  - "lib/autospec/*"
  - "lib/es6_module_transpiler/*"
diff --git a/.eslintignore b/.eslintignore
index 5b61bf6c51f..87cbecfae70 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -6,9 +6,7 @@ app/assets/javascripts/pagedown_custom.js
 app/assets/javascripts/vendor.js
 app/assets/javascripts/locales/i18n.js
 app/assets/javascripts/defer/html-sanitizer-bundle.js
-app/assets/javascripts/discourse/lib/Markdown.Editor.js
 app/assets/javascripts/ember-addons/
-jsapp/lib/Markdown.Editor.js
 lib/javascripts/locale/
 lib/javascripts/messageformat.js
 lib/javascripts/moment.js
diff --git a/app/assets/javascripts/discourse/components/composer-editor.js.es6 b/app/assets/javascripts/discourse/components/composer-editor.js.es6
new file mode 100644
index 00000000000..046e92fc11c
--- /dev/null
+++ b/app/assets/javascripts/discourse/components/composer-editor.js.es6
@@ -0,0 +1,354 @@
+import userSearch from 'discourse/lib/user-search';
+import { default as computed, on } from 'ember-addons/ember-computed-decorators';
+import { linkSeenMentions, fetchUnseenMentions } from 'discourse/lib/link-mentions';
+
+export default Ember.Component.extend({
+  classNames: ['wmd-controls'],
+  classNameBindings: [':wmd-controls', 'showPreview', 'showPreview::hide-preview'],
+
+  uploadProgress: 0,
+  showPreview: true,
+  _xhr: null,
+
+  @computed
+  uploadPlaceholder() {
+    return `[${I18n.t('uploading')}]() `;
+  },
+
+  @on('init')
+  _setupPreview() {
+    const val = (Discourse.Mobile.mobileView ? false : (this.keyValueStore.get('composer.showPreview') || 'true'));
+    this.set('showPreview', val === 'true');
+  },
+
+  @computed('showPreview')
+  toggleText: function(showPreview) {
+    return showPreview ? I18n.t('composer.hide_preview') : I18n.t('composer.show_preview');
+  },
+
+  @computed
+  markdownOptions() {
+    return {
+      lookupAvatarByPostNumber: (postNumber, topicId) => {
+        const topic = this.get('topic');
+        if (!topic) { return; }
+
+        const posts = topic.get('postStream.posts');
+        if (posts && topicId === topic.get('id')) {
+          const quotedPost = posts.findProperty("post_number", postNumber);
+          if (quotedPost) {
+            return Discourse.Utilities.tinyAvatar(quotedPost.get('avatar_template'));
+          }
+        }
+      }
+    };
+  },
+
+  @on('didInsertElement')
+  _composerEditorInit() {
+    const topicId = this.get('topic.id');
+    const template = this.container.lookup('template:user-selector-autocomplete.raw');
+    const $input = this.$('.d-editor-input');
+    $input.autocomplete({
+      template,
+      dataSource: term => userSearch({ term, topicId, includeGroups: true }),
+      key: "@",
+      transformComplete: v => v.username || v.usernames.join(", @")
+    });
+
+    // Focus on the body unless we have a title
+    if (!this.get('composer.canEditTitle') && !Discourse.Mobile.mobileView) {
+      this.$('.d-editor-input').putCursorAtEnd();
+    }
+
+    this._bindUploadTarget();
+    this.appEvents.trigger('composer:opened');
+  },
+
+  @computed('composer.reply', 'composer.replyLength', 'composer.missingReplyCharacters', 'composer.minimumPostLength', 'lastValidatedAt')
+  validation(reply, replyLength, missingReplyCharacters, minimumPostLength, lastValidatedAt) {
+    const postType = this.get('composer.post.post_type');
+    if (postType === this.site.get('post_types.small_action')) { return; }
+
+    let reason;
+    if (replyLength < 1) {
+      reason = I18n.t('composer.error.post_missing');
+    } else if (missingReplyCharacters > 0) {
+      reason = I18n.t('composer.error.post_length', {min: minimumPostLength});
+      const tl = Discourse.User.currentProp("trust_level");
+      if (tl === 0 || tl === 1) {
+        reason += "<br/>" + I18n.t('composer.error.try_like');
+      }
+    }
+
+    if (reason) {
+      return Discourse.InputValidation.create({ failed: true, reason, lastShownAt: lastValidatedAt });
+    }
+  },
+
+  _renderUnseen: function($preview, unseen) {
+    fetchUnseenMentions($preview, unseen, this.siteSettings).then(() => {
+      linkSeenMentions($preview, this.siteSettings);
+      this.trigger('previewRefreshed', $preview);
+    });
+  },
+
+  _resetUpload() {
+    this.setProperties({ uploadProgress: 0, isUploading: false });
+    this.set('composer.reply', this.get('composer.reply').replace(this.get('uploadPlaceholder'), ""));
+  },
+
+  _bindUploadTarget() {
+    this._unbindUploadTarget(); // in case it's still bound, let's clean it up first
+
+    const $element = this.$();;
+    const csrf = this.session.get('csrfToken');
+    const uploadPlaceholder = this.get('uploadPlaceholder');
+
+    $element.fileupload({
+      url: Discourse.getURL(`/uploads.json?client_id=${this.messageBus.clientId}&authenticity_token=${encodeURIComponent(csrf)}`),
+      dataType: "json",
+      pasteZone: $element,
+    });
+
+    $element.on('fileuploadsubmit', (e, data) => {
+      const isUploading = Discourse.Utilities.validateUploadedFiles(data.files);
+      data.formData = { type: "composer" };
+      this.setProperties({ uploadProgress: 0, isUploading });
+      return isUploading;
+    });
+
+    $element.on("fileuploadprogressall", (e, data) => {
+      this.set("uploadProgress", parseInt(data.loaded / data.total * 100, 10));
+    });
+
+    $element.on("fileuploadsend", (e, data) => {
+      // add upload placeholder
+      this.appEvents.trigger('composer:insert-text', uploadPlaceholder);
+
+      if (data.xhr) {
+        this._xhr = data.xhr();
+      }
+    });
+
+    $element.on("fileuploadfail", (e, data) => {
+      this._resetUpload();
+
+      const userCancelled = this._xhr && this._xhr._userCancelled;
+      this._xhr = null;
+
+      if (!userCancelled) {
+        Discourse.Utilities.displayErrorForUpload(data);
+      }
+    });
+
+    this.messageBus.subscribe("/uploads/composer", upload => {
+      // replace upload placeholder
+      if (upload && upload.url) {
+        if (!this._xhr || !this._xhr._userCancelled) {
+          const markdown = Discourse.Utilities.getUploadMarkdown(upload);
+          this.set('composer.reply', this.get('composer.reply').replace(uploadPlaceholder, markdown));
+        }
+      } else {
+        Discourse.Utilities.displayErrorForUpload(upload);
+      }
+
+      // reset upload state
+      this._resetUpload();
+    });
+
+    if (Discourse.Mobile.mobileView) {
+      this.$(".mobile-file-upload").on("click.uploader", function () {
+        // redirect the click on the hidden file input
+        $("#mobile-uploader").click();
+      });
+    }
+
+    this._firefoxPastingHack();
+  },
+
+  // Believe it or not pasting an image in Firefox doesn't work without this code
+  _firefoxPastingHack() {
+    const uaMatch = navigator.userAgent.match(/Firefox\/(\d+)\.\d/);
+    if (uaMatch && parseInt(uaMatch[1]) >= 24) {
+      this.$().append( Ember.$("<div id='contenteditable' contenteditable='true' style='height: 0; width: 0; overflow: hidden'></div>") );
+      this.$("textarea").off('keydown.contenteditable');
+      this.$("textarea").on('keydown.contenteditable', event => {
+        // Catch Ctrl+v / Cmd+v and hijack focus to a contenteditable div. We can't
+        // use the onpaste event because for some reason the paste isn't resumed
+        // after we switch focus, probably because it is being executed too late.
+        if ((event.ctrlKey || event.metaKey) && (event.keyCode === 86)) {
+          // Save the current textarea selection.
+          const textarea = this.$("textarea")[0];
+          const selectionStart = textarea.selectionStart;
+          const selectionEnd = textarea.selectionEnd;
+
+          // Focus the contenteditable div.
+          const contentEditableDiv = this.$('#contenteditable');
+          contentEditableDiv.focus();
+
+          // The paste doesn't finish immediately and we don't have any onpaste
+          // event, so wait for 100ms which _should_ be enough time.
+          setTimeout(() => {
+            const pastedImg  = contentEditableDiv.find('img');
+
+            if ( pastedImg.length === 1 ) {
+              pastedImg.remove();
+            }
+
+            // For restoring the selection.
+            textarea.focus();
+            const textareaContent = $(textarea).val(),
+                startContent = textareaContent.substring(0, selectionStart),
+                endContent = textareaContent.substring(selectionEnd);
+
+            const restoreSelection = function(pastedText) {
+              $(textarea).val( startContent + pastedText + endContent );
+              textarea.selectionStart = selectionStart + pastedText.length;
+              textarea.selectionEnd = textarea.selectionStart;
+            };
+
+            if (contentEditableDiv.html().length > 0) {
+              // If the image wasn't the only pasted content we just give up and
+              // fall back to the original pasted text.
+              contentEditableDiv.find("br").replaceWith("\n");
+              restoreSelection(contentEditableDiv.text());
+            } else {
+              // Depending on how the image is pasted in, we may get either a
+              // normal URL or a data URI. If we get a data URI we can convert it
+              // to a Blob and upload that, but if it is a regular URL that
+              // operation is prevented for security purposes. When we get a regular
+              // URL let's just create an <img> tag for the image.
+              const imageSrc = pastedImg.attr('src');
+
+              if (imageSrc.match(/^data:image/)) {
+                // Restore the cursor position, and remove any selected text.
+                restoreSelection("");
+
+                // Create a Blob to upload.
+                const image = new Image();
+                image.onload = function() {
+                  // Create a new canvas.
+                  const canvas = document.createElementNS('http://www.w3.org/1999/xhtml', 'canvas');
+                  canvas.height = image.height;
+                  canvas.width = image.width;
+                  const ctx = canvas.getContext('2d');
+                  ctx.drawImage(image, 0, 0);
+
+                  canvas.toBlob(blob => this.$().fileupload('add', {files: blob}));
+                };
+                image.src = imageSrc;
+              } else {
+                restoreSelection("<img src='" + imageSrc + "'>");
+              }
+            }
+
+            contentEditableDiv.html('');
+          }, 100);
+        }
+      });
+    }
+  },
+
+  @on('willDestroyElement')
+  _unbindUploadTarget() {
+    this.$(".mobile-file-upload").off("click.uploader");
+    this.messageBus.unsubscribe("/uploads/composer");
+    const $uploadTarget = this.$();
+    try { $uploadTarget.fileupload("destroy"); }
+    catch (e) { /* wasn't initialized yet */ }
+    $uploadTarget.off();
+  },
+
+  @on('willDestroyElement')
+  _composerClosed() {
+    Ember.run.next(() => {
+      $('#main-outlet').css('padding-bottom', 0);
+      // need to wait a bit for the "slide down" transition of the composer
+      Ember.run.later(() => this.appEvents.trigger("composer:closed"), 400);
+    });
+  },
+
+  actions: {
+    importQuote(toolbarEvent) {
+      this.sendAction('importQuote', toolbarEvent);
+    },
+
+    cancelUpload() {
+      if (this._xhr) {
+        this._xhr._userCancelled = true;
+        this._xhr.abort();
+        this._resetUpload();
+      }
+      this._resetUpload();
+    },
+
+    showOptions() {
+      const myPos = this.$().position();
+      const buttonPos = this.$('.options').position();
+
+      this.sendAction('showOptions', { position: "absolute",
+                                       left: myPos.left + buttonPos.left,
+                                       top: myPos.top + buttonPos.top });
+    },
+
+    showUploadModal(toolbarEvent) {
+      this.sendAction('showUploadSelector', toolbarEvent);
+    },
+
+    togglePreview() {
+      this.toggleProperty('showPreview');
+      this.keyValueStore.set({ key: 'composer.showPreview', value: this.get('showPreview') });
+    },
+
+    extraButtons(toolbar) {
+      toolbar.addButton({
+        id: 'quote',
+        group: 'fontStyles',
+        icon: 'comment-o',
+        sendAction: 'importQuote',
+        title: 'composer.quote_post_title',
+        unshift: true
+      });
+
+      toolbar.addButton({
+        id: 'upload',
+        group: 'insertions',
+        icon: 'upload',
+        title: 'upload',
+        sendAction: 'showUploadModal'
+      });
+
+      if (this.get('canWhisper')) {
+        toolbar.addButton({
+          id: 'options',
+          group: 'extras',
+          icon: 'gear',
+          title: 'composer.options',
+          sendAction: 'showOptions'
+        });
+      }
+    },
+
+    previewUpdated($preview) {
+      // Paint mentions
+      const unseen = linkSeenMentions($preview, this.siteSettings);
+      if (unseen.length) {
+        Ember.run.debounce(this, this._renderUnseen, $preview, unseen, 500);
+      }
+
+      const post = this.get('composer.post');
+      let refresh = false;
+
+      // If we are editing a post, we'll refresh its contents once. This is a feature that
+      // allows a user to refresh its contents once.
+      if (post && !post.get('refreshedPost')) {
+        refresh = true;
+        post.set('refreshedPost', true);
+      }
+
+      // Paint oneboxes
+      $('a.onebox', $preview).each((i, e) => Discourse.Onebox.load(e, refresh));
+    },
+  }
+});
diff --git a/app/assets/javascripts/discourse/components/composer-text-area.js.es6 b/app/assets/javascripts/discourse/components/composer-text-area.js.es6
deleted file mode 100644
index 37ac9b1cd98..00000000000
--- a/app/assets/javascripts/discourse/components/composer-text-area.js.es6
+++ /dev/null
@@ -1,15 +0,0 @@
-export default Ember.TextArea.extend({
-  classNameBindings: [':wmd-input'],
-
-  placeholder: function() {
-    return I18n.t('composer.reply_placeholder');
-  }.property('placeholderKey'),
-
-  _signalParentInsert: function() {
-    this.get('parentView').childDidInsertElement(this);
-  }.on('didInsertElement'),
-
-  _signalParentDestroy: function() {
-    this.get('parentView').childWillDestroyElement(this);
-  }.on('willDestroyElement')
-});
diff --git a/app/assets/javascripts/discourse/components/composer-title.js.es6 b/app/assets/javascripts/discourse/components/composer-title.js.es6
new file mode 100644
index 00000000000..5a1968ad4c9
--- /dev/null
+++ b/app/assets/javascripts/discourse/components/composer-title.js.es6
@@ -0,0 +1,29 @@
+import { default as computed, on } from 'ember-addons/ember-computed-decorators';
+
+export default Ember.Component.extend({
+  classNames: ['title-input'],
+
+  @on('didInsertElement')
+  _focusOnReply() {
+    if (!Discourse.Mobile.mobileView) {
+      this.$('input').putCursorAtEnd();
+    }
+  },
+
+  @computed('composer.titleLength', 'composer.missingTitleCharacters', 'composer.minimumTitleLength', 'lastValidatedAt')
+  validation(titleLength, missingTitleChars, minimumTitleLength, lastValidatedAt) {
+
+    let reason;
+    if (titleLength < 1) {
+      reason = I18n.t('composer.error.title_missing');
+    } else if (missingTitleChars > 0) {
+      reason = I18n.t('composer.error.title_too_short', {min: minimumTitleLength});
+    } else if (titleLength > this.siteSettings.max_topic_title_length) {
+      reason = I18n.t('composer.error.title_too_long', {max: this.siteSettings.max_topic_title_length});
+    }
+
+    if (reason) {
+      return Discourse.InputValidation.create({ failed: true, reason, lastShownAt: lastValidatedAt });
+    }
+  }
+});
diff --git a/app/assets/javascripts/discourse/components/d-editor.js.es6 b/app/assets/javascripts/discourse/components/d-editor.js.es6
index 4d26eb3e436..14c83b14081 100644
--- a/app/assets/javascripts/discourse/components/d-editor.js.es6
+++ b/app/assets/javascripts/discourse/components/d-editor.js.es6
@@ -1,6 +1,6 @@
 /*global Mousetrap:true */
 import loadScript from 'discourse/lib/load-script';
-import { default as property, on } from 'ember-addons/ember-computed-decorators';
+import { default as computed, on } from 'ember-addons/ember-computed-decorators';
 import { showSelector } from "discourse/lib/emoji/emoji-toolbar";
 
 // Our head can be a static string or a function that returns a string
@@ -111,6 +111,10 @@ Toolbar.prototype.addButton = function(button) {
     perform: button.perform || Ember.K
   };
 
+  if (button.sendAction) {
+    createdButton.sendAction = button.sendAction;
+  }
+
   const title = I18n.t(button.title || `composer.${button.id}_title`);
   if (button.shortcut) {
     const mac = /Mac|iPod|iPhone|iPad/.test(navigator.platform);
@@ -130,7 +134,11 @@ Toolbar.prototype.addButton = function(button) {
     createdButton.title = title;
   }
 
-  g.buttons.push(createdButton);
+  if (button.unshift) {
+    g.buttons.unshift(createdButton);
+  } else {
+    g.buttons.push(createdButton);
+  }
 };
 
 export function onToolbarCreate(func) {
@@ -144,9 +152,16 @@ export default Ember.Component.extend({
   link: '',
   lastSel: null,
 
+  @computed('placeholder')
+  placeholderTranslated(placeholder) {
+    if (placeholder) return I18n.t(placeholder);
+    return null;
+  },
+
   @on('didInsertElement')
   _startUp() {
     this._applyEmojiAutocomplete();
+
     loadScript('defer/html-sanitizer-bundle').then(() => this.set('ready', true));
 
     const shortcuts = this.get('toolbar.shortcuts');
@@ -156,27 +171,52 @@ export default Ember.Component.extend({
         this.send(button.action, button);
       });
     });
+
+    // disable clicking on links in the preview
+    this.$('.d-editor-preview').on('click.preview', e => {
+      e.preventDefault();
+      return false;
+    });
+
+    this.appEvents.on('composer:insert-text', text => {
+      this._addText(this._getSelected(), text);
+    });
   },
 
   @on('willDestroyElement')
   _shutDown() {
+    this.appEvents.off('composer:insert-text');
+
     Ember.keys(this.get('toolbar.shortcuts')).forEach(sc => {
       Mousetrap(this.$('.d-editor-input')[0]).unbind(sc);
     });
+    this.$('.d-editor-preview').off('click.preview');
   },
 
-  @property
+  @computed
   toolbar() {
     const toolbar = new Toolbar();
     _createCallbacks.forEach(cb => cb(toolbar));
+    this.sendAction('extraButtons', toolbar);
     return toolbar;
   },
 
-  @property('ready', 'value')
+  @computed('ready', 'value')
   preview(ready, value) {
     if (!ready) { return; }
 
-    const text = Discourse.Dialect.cook(value || "", {sanitize: true});
+    const markdownOptions = this.get('markdownOptions') || {};
+    markdownOptions.sanitize = true;
+
+    const text = Discourse.Dialect.cook(value || "", markdownOptions);
+    Ember.run.scheduleOnce('afterRender', () => {
+      if (this._state !== "inDOM") { return; }
+      const $preview = this.$('.d-editor-preview');
+      if ($preview.length === 0) return;
+
+      this.sendAction('previewUpdated', $preview);
+    });
+
     return text ? text : "";
   },
 
@@ -339,12 +379,18 @@ export default Ember.Component.extend({
   actions: {
     toolbarButton(button) {
       const selected = this._getSelected();
-      button.perform({
+      const toolbarEvent = {
         selected,
         applySurround: (head, tail, exampleKey) => this._applySurround(selected, head, tail, exampleKey),
         applyList: (head, exampleKey) => this._applyList(selected, head, exampleKey),
         addText: text => this._addText(selected, text)
-      });
+      };
+
+      if (button.sendAction) {
+        return this.sendAction(button.sendAction, toolbarEvent);
+      } else {
+        button.perform(toolbarEvent);
+      }
     },
 
     showLinkModal() {
diff --git a/app/assets/javascripts/discourse/components/edit-category-topic-template.js.es6 b/app/assets/javascripts/discourse/components/edit-category-topic-template.js.es6
index 34419b477b1..308d3223eab 100644
--- a/app/assets/javascripts/discourse/components/edit-category-topic-template.js.es6
+++ b/app/assets/javascripts/discourse/components/edit-category-topic-template.js.es6
@@ -5,7 +5,7 @@ export default buildCategoryPanel('topic-template', {
     if (this.get('activeTab')) {
       const self = this;
       Ember.run.schedule('afterRender', function() {
-        self.$('.wmd-input').focus();
+        self.$('.d-editor-input').focus();
       });
     }
   }.observes('activeTab')
diff --git a/app/assets/javascripts/discourse/components/image-uploader.js.es6 b/app/assets/javascripts/discourse/components/image-uploader.js.es6
index 3fc6650a47e..08359fa8695 100644
--- a/app/assets/javascripts/discourse/components/image-uploader.js.es6
+++ b/app/assets/javascripts/discourse/components/image-uploader.js.es6
@@ -1,10 +1,10 @@
-import property from 'ember-addons/ember-computed-decorators';
+import computed from 'ember-addons/ember-computed-decorators';
 import UploadMixin from "discourse/mixins/upload";
 
 export default Em.Component.extend(UploadMixin, {
   classNames: ["image-uploader"],
 
-  @property('imageUrl')
+  @computed('imageUrl')
   backgroundStyle(imageUrl) {
     if (Em.isNone(imageUrl)) { return; }
     return `background-image: url(${imageUrl})`.htmlSafe();
diff --git a/app/assets/javascripts/discourse/components/popup-input-tip.js.es6 b/app/assets/javascripts/discourse/components/popup-input-tip.js.es6
index 51725abc09e..ce2dc31c532 100644
--- a/app/assets/javascripts/discourse/components/popup-input-tip.js.es6
+++ b/app/assets/javascripts/discourse/components/popup-input-tip.js.es6
@@ -1,9 +1,9 @@
 import StringBuffer from 'discourse/mixins/string-buffer';
 import { iconHTML } from 'discourse/helpers/fa-icon';
-import { observes } from 'ember-addons/ember-computed-decorators';
+import { default as computed, observes } from 'ember-addons/ember-computed-decorators';
 
 export default Ember.Component.extend(StringBuffer, {
-  classNameBindings: [':popup-tip', 'good', 'bad', 'shownAt::hide'],
+  classNameBindings: [':popup-tip', 'good', 'bad', 'lastShownAt::hide'],
   animateAttribute: null,
   bouncePixels: 6,
   bounceDelay: 100,
@@ -16,9 +16,14 @@ export default Ember.Component.extend(StringBuffer, {
   bad: Ember.computed.alias("validation.failed"),
   good: Ember.computed.not("bad"),
 
-  @observes("shownAt")
+  @computed('shownAt', 'validation.lastShownAt')
+  lastShownAt(shownAt, lastShownAt) {
+    return shownAt || lastShownAt;
+  },
+
+  @observes('lastShownAt')
   bounce() {
-    if (this.get("shownAt")) {
+    if (this.get("lastShownAt")) {
       var $elem = this.$();
       if (!this.animateAttribute) {
         this.animateAttribute = $elem.css('left') === 'auto' ? 'right' : 'left';
diff --git a/app/assets/javascripts/discourse/components/post-gutter.js.es6 b/app/assets/javascripts/discourse/components/post-gutter.js.es6
index f4ca4cac6f7..c545f1c0b7b 100644
--- a/app/assets/javascripts/discourse/components/post-gutter.js.es6
+++ b/app/assets/javascripts/discourse/components/post-gutter.js.es6
@@ -2,7 +2,7 @@ const MAX_SHOWN = 5;
 
 import StringBuffer from 'discourse/mixins/string-buffer';
 import { iconHTML } from 'discourse/helpers/fa-icon';
-import property from 'ember-addons/ember-computed-decorators';
+import computed from 'ember-addons/ember-computed-decorators';
 
 const { get, isEmpty, Component } = Ember;
 
@@ -12,7 +12,7 @@ export default Component.extend(StringBuffer, {
   rerenderTriggers: ['expanded'],
 
   // Roll up links to avoid duplicates
-  @property('links')
+  @computed('links')
   collapsed(links) {
     const seen = {};
     const result = [];
diff --git a/app/assets/javascripts/discourse/controllers/composer.js.es6 b/app/assets/javascripts/discourse/controllers/composer.js.es6
index b8328a87f3a..92b51cc9591 100644
--- a/app/assets/javascripts/discourse/controllers/composer.js.es6
+++ b/app/assets/javascripts/discourse/controllers/composer.js.es6
@@ -1,9 +1,8 @@
-import { setting } from 'discourse/lib/computed';
 import DiscourseURL from 'discourse/lib/url';
 import Quote from 'discourse/lib/quote';
 import Draft from 'discourse/models/draft';
 import Composer from 'discourse/models/composer';
-import computed from 'ember-addons/ember-computed-decorators';
+import { default as computed, observes } from 'ember-addons/ember-computed-decorators';
 
 function loadDraft(store, opts) {
   opts = opts || {};
@@ -50,17 +49,17 @@ export default Ember.Controller.extend({
 
   showEditReason: false,
   editReason: null,
-  maxTitleLength: setting('max_topic_title_length'),
   scopedCategoryId: null,
   similarTopics: null,
   similarTopicsMessage: null,
   lastSimilaritySearch: null,
   optionsVisible: false,
 
-  topic: null,
+  lastValidatedAt: null,
 
-  // TODO: Remove this, very bad
-  view: null,
+  isUploading: false,
+
+  topic: null,
 
   _initializeSimilar: function() {
     this.set('similarTopics', []);
@@ -109,7 +108,7 @@ export default Ember.Controller.extend({
     },
 
     // Import a quote from the post
-    importQuote() {
+    importQuote(toolbarEvent) {
       const postStream = this.get('topic.postStream');
       let postId = this.get('model.post.id');
 
@@ -135,7 +134,7 @@ export default Ember.Controller.extend({
 
         return this.store.find('post', postId).then(function(post) {
           const quote = Quote.build(post, post.get("raw"), {raw: true, full: true});
-          composer.appendBlockAtCursor(quote);
+          toolbarEvent.addText(quote);
           composer.set('model.loading', false);
         });
       }
@@ -173,39 +172,10 @@ export default Ember.Controller.extend({
 
   },
 
-  appendText(text, opts) {
-    const c = this.get('model');
-    if (c) {
-      opts = opts || {};
-      const wmd = $('.wmd-input'),
-            val = wmd.val() || '',
-            position = opts.position === "cursor" ? wmd.caret() : val.length,
-            caret = c.appendText(text, position, opts);
-
-      if (wmd[0]) {
-        Em.run.next(() => Discourse.Utilities.setCaretPosition(wmd[0], caret));
-      }
-    }
-  },
-
-  appendTextAtCursor(text, opts) {
-    opts = opts || {};
-    opts.position = "cursor";
-    this.appendText(text, opts);
-  },
-
-  appendBlockAtCursor(text, opts) {
-    opts = opts || {};
-    opts.position = "cursor";
-    opts.block = true;
-    this.appendText(text, opts);
-  },
-
   categories: function() {
     return Discourse.Category.list();
   }.property(),
 
-
   toggle() {
     this.closeAutocomplete();
     switch (this.get('model.composeState')) {
@@ -225,7 +195,7 @@ export default Ember.Controller.extend({
     return false;
   },
 
-  disableSubmit: Ember.computed.or("model.loading", "view.isUploading"),
+  disableSubmit: Ember.computed.or("model.loading", "isUploading"),
 
   save(force) {
     const composer = this.get('model');
@@ -237,12 +207,7 @@ export default Ember.Controller.extend({
     }
 
     if (composer.get('cantSubmitPost')) {
-      const now = Date.now();
-      this.setProperties({
-        'view.showTitleTip': now,
-        'view.showCategoryTip': now,
-        'view.showReplyTip': now
-      });
+      this.set('lastValidatedAt', Date.now());
       return;
     }
 
@@ -291,10 +256,18 @@ export default Ember.Controller.extend({
     var staged = false;
     const disableJumpReply = Discourse.User.currentProp('disable_jump_reply');
 
-    const promise = composer.save({
-      imageSizes: this.get('view').imageSizes(),
-      editReason: this.get("editReason")
-    }).then(function(result) {
+    // TODO: This should not happen in model
+    const imageSizes = {};
+    $('#reply-control .d-editor-preview img').each((i, e) => {
+      const $img = $(e);
+      const src = $img.prop('src');
+
+      if (src && src.length) {
+        imageSizes[src] = { width: $img.width(), height: $img.height() };
+      }
+    });
+
+    const promise = composer.save({ imageSizes, editReason: this.get("editReason")}).then(function(result) {
       if (result.responseJson.action === "enqueued") {
         self.send('postWasEnqueued', result.responseJson);
         self.destroyDraft();
@@ -366,8 +339,8 @@ export default Ember.Controller.extend({
     // We don't care about similar topics unless creating a topic
     if (!this.get('model.creatingTopic')) { return; }
 
-    let body = this.get('model.reply');
-    const title = this.get('model.title');
+    let body = this.get('model.reply') || '';
+    const title = this.get('model.title') || '';
 
     // Ensure the fields are of the minimum length
     if (body.length < Discourse.SiteSettings.min_body_similar_length) { return; }
@@ -405,11 +378,6 @@ export default Ember.Controller.extend({
     });
   },
 
-  saveDraft() {
-    const model = this.get('model');
-    if (model) { model.saveDraft(); }
-  },
-
   /**
     Open the composer view
 
@@ -502,7 +470,7 @@ export default Ember.Controller.extend({
     composerModel.set('composeState', Discourse.Composer.OPEN);
     composerModel.set('isWarning', false);
 
-    if (opts.topicTitle && opts.topicTitle.length <= this.get('maxTitleLength')) {
+    if (opts.topicTitle && opts.topicTitle.length <= this.siteSettings.max_topic_title_length) {
       this.set('model.title', opts.topicTitle);
     }
 
@@ -572,7 +540,6 @@ export default Ember.Controller.extend({
     });
   },
 
-
   shrink() {
     if (this.get('model.replyDirty')) {
       this.collapse();
@@ -581,22 +548,34 @@ export default Ember.Controller.extend({
     }
   },
 
+  _saveDraft() {
+    const model = this.get('model');
+    if (model) { model.saveDraft(); };
+  },
+
+  @observes('model.reply', 'model.title')
+  _shouldSaveDraft() {
+    Ember.run.debounce(this, this._saveDraft, 2000);
+  },
+
+  @computed('model.categoryId', 'lastValidatedAt')
+  categoryValidation(categoryId, lastValidatedAt) {
+    if( !this.siteSettings.allow_uncategorized_topics && !categoryId) {
+      return Discourse.InputValidation.create({ failed: true, reason: I18n.t('composer.error.category_missing'), lastShownAt: lastValidatedAt });
+    }
+  },
+
   collapse() {
-    this.saveDraft();
+    this._saveDraft();
     this.set('model.composeState', Discourse.Composer.DRAFT);
   },
 
   close() {
-    this.setProperties({
-      model: null,
-      'view.showTitleTip': false,
-      'view.showCategoryTip': false,
-      'view.showReplyTip': false
-    });
+    this.setProperties({ model: null, lastValidatedAt: null });
   },
 
   closeAutocomplete() {
-    $('.wmd-input').autocomplete({ cancel: true });
+    $('.d-editor-input').autocomplete({ cancel: true });
   },
 
   showOptions() {
diff --git a/app/assets/javascripts/discourse/controllers/quote-button.js.es6 b/app/assets/javascripts/discourse/controllers/quote-button.js.es6
index 620decb81da..2ad413846dd 100644
--- a/app/assets/javascripts/discourse/controllers/quote-button.js.es6
+++ b/app/assets/javascripts/discourse/controllers/quote-button.js.es6
@@ -1,6 +1,6 @@
 import loadScript from 'discourse/lib/load-script';
 import Quote from 'discourse/lib/quote';
-import property from 'ember-addons/ember-computed-decorators';
+import computed from 'ember-addons/ember-computed-decorators';
 
 export default Ember.Controller.extend({
   needs: ['topic', 'composer'],
@@ -9,7 +9,7 @@ export default Ember.Controller.extend({
     loadScript('defer/html-sanitizer-bundle');
   }.on('init'),
 
-  @property('buffer', 'postId')
+  @computed('buffer', 'postId')
   post(buffer, postId) {
     if (!postId || Ember.isEmpty(buffer)) { return null; }
 
@@ -135,7 +135,7 @@ export default Ember.Controller.extend({
     const quotedText = Quote.build(post, buffer);
     composerOpts.quote = quotedText;
     if (composerController.get('content.viewOpen') || composerController.get('content.viewDraft')) {
-      composerController.appendBlockAtCursor(quotedText.trim());
+      this.appEvents.trigger('composer:insert-text', quotedText.trim());
     } else {
       composerController.open(composerOpts);
     }
diff --git a/app/assets/javascripts/discourse/controllers/topic.js.es6 b/app/assets/javascripts/discourse/controllers/topic.js.es6
index e0e480953f1..95ebbe4b6f6 100644
--- a/app/assets/javascripts/discourse/controllers/topic.js.es6
+++ b/app/assets/javascripts/discourse/controllers/topic.js.es6
@@ -3,7 +3,6 @@ import SelectedPostsCount from 'discourse/mixins/selected-posts-count';
 import { spinnerHTML } from 'discourse/helpers/loading-spinner';
 import Topic from 'discourse/models/topic';
 import Quote from 'discourse/lib/quote';
-import { setting } from 'discourse/lib/computed';
 import { popupAjaxError } from 'discourse/lib/ajax-error';
 import computed from 'ember-addons/ember-computed-decorators';
 
@@ -24,8 +23,6 @@ export default Ember.Controller.extend(SelectedPostsCount, BufferedContent, {
   showRecover: Em.computed.and('model.deleted', 'model.details.can_recover'),
   isFeatured: Em.computed.or("model.pinned_at", "model.isBanner"),
 
-  maxTitleLength: setting('max_topic_title_length'),
-
   _titleChanged: function() {
     const title = this.get('model.title');
     if (!Ember.isEmpty(title)) {
diff --git a/app/assets/javascripts/discourse/controllers/upload-selector.js.es6 b/app/assets/javascripts/discourse/controllers/upload-selector.js.es6
index f0a7d67fcd8..694722ccd76 100644
--- a/app/assets/javascripts/discourse/controllers/upload-selector.js.es6
+++ b/app/assets/javascripts/discourse/controllers/upload-selector.js.es6
@@ -1,14 +1,58 @@
 import ModalFunctionality from 'discourse/mixins/modal-functionality';
+import { default as computed } from 'ember-addons/ember-computed-decorators';
+
+export function uploadTranslate(key, options) {
+  options = options || {};
+  if (Discourse.Utilities.allowsAttachments()) { key += "_with_attachments"; }
+  return I18n.t(`upload_selector.${key}`, options);
+}
 
 export default Ember.Controller.extend(ModalFunctionality, {
   showMore: false,
   local: true,
+  imageUrl: null,
+  imageLink: null,
   remote: Ember.computed.not("local"),
 
+  @computed
+  uploadIcon() {
+    return Discourse.Utilities.allowsAttachments() ? "upload" : "picture-o";
+  },
+
+  @computed('controller.local')
+  tip(local) {
+    const source = local ? "local" : "remote";
+    const authorized_extensions = Discourse.Utilities.authorizesAllExtensions() ? "" : `(${Discourse.Utilities.authorizedExtensions()})`;
+    return uploadTranslate(`${source}_tip`, { authorized_extensions });
+  },
+
   actions: {
-    useLocal() { this.setProperties({ local: true, showMore: false}); },
-    useRemote() { this.set("local", false); },
-    toggleShowMore() { this.toggleProperty("showMore"); }
+    upload() {
+      if (this.get('local')) {
+        $('#reply-control').fileupload('add', { fileInput: $('#filename-input') });
+      } else {
+        const imageUrl = this.get('imageUrl') || '';
+        const imageLink = this.get('imageLink') || '';
+        const toolbarEvent = this.get('toolbarEvent');
+
+        if (this.get('showMore') && imageLink.length > 3) {
+          toolbarEvent.addText(`[![](${imageUrl})](${imageLink})`);
+        } else {
+          toolbarEvent.addText(imageUrl);
+        }
+        this.send('closeModal');
+      }
+    },
+
+    useLocal() {
+      this.setProperties({ local: true, showMore: false});
+    },
+    useRemote() {
+      this.set("local", false);
+    },
+    toggleShowMore() {
+      this.toggleProperty("showMore");
+    }
   }
 
 });
diff --git a/app/assets/javascripts/discourse/initializers/enable-emoji.js.es6 b/app/assets/javascripts/discourse/initializers/enable-emoji.js.es6
index 7120a3e3e0a..2ec1843c408 100644
--- a/app/assets/javascripts/discourse/initializers/enable-emoji.js.es6
+++ b/app/assets/javascripts/discourse/initializers/enable-emoji.js.es6
@@ -1,4 +1,3 @@
-import { showSelector } from "discourse/lib/emoji/emoji-toolbar";
 import { onToolbarCreate } from 'discourse/components/d-editor';
 
 export default {
@@ -8,7 +7,6 @@ export default {
     const siteSettings = container.lookup('site-settings:main');
 
     if (siteSettings.enable_emoji) {
-
       onToolbarCreate(toolbar => {
         toolbar.addButton({
           id: 'emoji',
@@ -20,20 +18,6 @@ export default {
         });
       });
 
-      window.PagedownCustom.appendButtons.push({
-        id: 'wmd-emoji-button',
-        description: I18n.t("composer.emoji"),
-        execute() {
-          showSelector({
-            container,
-            onSelect(title) {
-              const composerController = container.lookup('controller:composer');
-              composerController.appendTextAtCursor(`:${title}:`, {space: true});
-            },
-          });
-        }
-      });
-
       // enable plugin emojis
       Discourse.Emoji.applyCustomEmojis();
     }
diff --git a/app/assets/javascripts/discourse/initializers/ensure-max-image-dimensions.js.es6 b/app/assets/javascripts/discourse/initializers/ensure-max-image-dimensions.js.es6
index 012fc98135f..746abc38f48 100644
--- a/app/assets/javascripts/discourse/initializers/ensure-max-image-dimensions.js.es6
+++ b/app/assets/javascripts/discourse/initializers/ensure-max-image-dimensions.js.es6
@@ -18,6 +18,6 @@ export default {
     const style = 'max-width:' + width + 'px;' +
                   'max-height:' + height + 'px;';
 
-    $('<style id="image-sizing-hack">#reply-control .wmd-preview img:not(.thumbnail), .cooked img:not(.thumbnail) {' + style + '}</style>').appendTo('head');
+    $('<style id="image-sizing-hack">#reply-control .d-editor-preview img:not(.thumbnail), .cooked img:not(.thumbnail) {' + style + '}</style>').appendTo('head');
   }
 };
diff --git a/app/assets/javascripts/discourse/lib/Markdown.Editor.js b/app/assets/javascripts/discourse/lib/Markdown.Editor.js
deleted file mode 100644
index 2dd0acaef3c..00000000000
--- a/app/assets/javascripts/discourse/lib/Markdown.Editor.js
+++ /dev/null
@@ -1,2190 +0,0 @@
-// needs Markdown.Converter.js at the moment
-
-
-// To insert extra buttons:
-//
-//  Before this file is required, define a PagedownCustom object. Give it an attribtue of insertButtons, which is an array
-//  of the buttons you want to insert. For example:
-//
-//      window.PagedownCustom = {
-//        insertButtons: [
-//          {
-//            id: 'wmd-bark',
-//            description: 'Bark',
-//            execute: function() {
-//              return alert('woof!');
-//            }
-//          }
-//        ]
-//      };
-//
-// To extend actions:
-//
-//      window.PagedownCustom = {
-//          customActions: {
-//             "doBlockquote": function(chunk, postProcessing, oldDoBlockquote) {
-//               console.log('custom blockquote called!');
-//               return oldDoBlockquote.call(this, chunk, postProcessing);
-//             }
-//          }
-//      };
-
-
-(function () {
-
-    var util = {},
-        position = {},
-        ui = {},
-        doc = window.document,
-        re = window.RegExp,
-        nav = window.navigator,
-        SETTINGS = { lineLength: 72 };
-
-
-    var defaultsStrings = {
-        bold: "Strong <strong> Ctrl+B",
-        boldexample: "strong text",
-
-        italic: "Emphasis <em> Ctrl+I",
-        italicexample: "emphasized text",
-
-        link: "Hyperlink <a> Ctrl+L",
-        linkdescription: "enter link description here",
-        linkdialog: "<p><b>Insert Hyperlink</b></p><p>http://example.com/ \"optional title\"</p>",
-
-        quote: "Blockquote <blockquote> Ctrl+Q",
-        quoteexample: "Blockquote",
-
-        code: "Code Sample <pre><code> Ctrl+K",
-        codeexample: "enter code here",
-
-        image: "Image <img> Ctrl+G",
-        imagedescription: "enter image description here",
-        imagedialog: "<p><b>Insert Image</b></p><p>http://example.com/images/diagram.jpg \"optional title\"<br><br>Need <a href='http://www.google.com/search?q=free+image+hosting' target='_blank'>free image hosting?</a></p>",
-
-        olist: "Numbered List <ol> Ctrl+O",
-        ulist: "Bulleted List <ul> Ctrl+U",
-        litem: "List item",
-
-        heading: "Heading <h1>/<h2> Ctrl+H",
-        headingexample: "Heading",
-
-        hr: "Horizontal Rule <hr> Ctrl+R",
-
-        undo: "Undo - Ctrl+Z",
-        redo: "Redo - Ctrl+Y",
-        redomac: "Redo - Ctrl+Shift+Z",
-
-        help: "Markdown Editing Help"
-    };
-
-
-    // -------------------------------------------------------------------
-    //  YOUR CHANGES GO HERE
-    //
-    // I've tried to localize the things you are likely to change to
-    // this area.
-    // -------------------------------------------------------------------
-
-    // The default text that appears in the dialog input box when entering
-    // links.
-    var imageDefaultText = "http://";
-    var linkDefaultText = "http://";
-
-    // -------------------------------------------------------------------
-    //  END OF YOUR CHANGES
-    // -------------------------------------------------------------------
-
-    // options, if given, can have the following properties:
-    //   options.helpButton = { handler: yourEventHandler }
-    //   options.strings = { italicexample: "slanted text" }
-    // `yourEventHandler` is the click handler for the help button.
-    // If `options.helpButton` isn't given, not help button is created.
-    // `options.strings` can have any or all of the same properties as
-    // `defaultStrings` above, so you can just override some string displayed
-    // to the user on a case-by-case basis, or translate all strings to
-    // a different language.
-    //
-    // For backwards compatibility reasons, the `options` argument can also
-    // be just the `helpButton` object, and `strings.help` can also be set via
-    // `helpButton.title`. This should be considered legacy.
-    //
-    // The constructed editor object has the methods:
-    // - getConverter() returns the markdown converter object that was passed to the constructor
-    // - run() actually starts the editor; should be called after all necessary plugins are registered. Calling this more than once is a no-op.
-    // - refreshPreview() forces the preview to be updated. This method is only available after run() was called.
-    Markdown.Editor = function (markdownConverter, idPostfix, options) {
-
-        options = options || {};
-
-        if (typeof options.handler === "function") { //backwards compatible behavior
-            options = { helpButton: options };
-        }
-        options.strings = options.strings || {};
-        if (options.helpButton) {
-            options.strings.help = options.strings.help || options.helpButton.title;
-        }
-        var getString = function (identifier) { return options.strings[identifier] || defaultsStrings[identifier]; }
-
-        idPostfix = idPostfix || "";
-
-        var hooks = this.hooks = new Markdown.HookCollection();
-        hooks.addNoop("onPreviewRefresh");       // called with no arguments after the preview has been refreshed
-        hooks.addNoop("postBlockquoteCreation"); // called with the user's selection *after* the blockquote was created; should return the actual to-be-inserted text
-        hooks.addFalse("insertImageDialog");     /* called with one parameter: a callback to be called with the URL of the image. If the application creates
-                                                  * its own image insertion dialog, this hook should return true, and the callback should be called with the chosen
-                                                  * image url (or null if the user cancelled). If this hook returns false, the default dialog will be used.
-                                                  */
-
-        this.getConverter = function () { return markdownConverter; }
-
-        var that = this,
-            panels;
-
-        this.run = function () {
-            if (panels)
-                return; // already initialized
-
-            panels = new PanelCollection(options.containerElement);
-            var commandManager = new CommandManager(hooks, getString);
-            var previewManager = new PreviewManager(markdownConverter, panels, function () { hooks.onPreviewRefresh(); });
-            var undoManager, uiManager;
-
-            if (false && !/\?noundo/.test(doc.location.href)) {
-                undoManager = new UndoManager(function () {
-                    previewManager.refresh();
-                    if (uiManager) // not available on the first call
-                        uiManager.setUndoRedoButtonStates();
-                }, panels);
-                this.textOperation = function (f) {
-                    undoManager.setCommandMode();
-                    f();
-                    that.refreshPreview();
-                }
-            }
-
-            uiManager = new UIManager(idPostfix, panels, undoManager, previewManager, commandManager, options.helpButton, getString, options);
-            uiManager.setUndoRedoButtonStates();
-
-            var forceRefresh = that.refreshPreview = function () { previewManager.refresh(true); };
-
-            forceRefresh();
-        };
-
-    }
-
-    // before: contains all the text in the input box BEFORE the selection.
-    // after: contains all the text in the input box AFTER the selection.
-    function Chunks() { }
-
-    // startRegex: a regular expression to find the start tag
-    // endRegex: a regular expresssion to find the end tag
-    Chunks.prototype.findTags = function (startRegex, endRegex) {
-
-        var chunkObj = this;
-        var regex;
-
-        if (startRegex) {
-
-            regex = util.extendRegExp(startRegex, "", "$");
-
-            this.before = this.before.replace(regex,
-                function (match) {
-                    chunkObj.startTag = chunkObj.startTag + match;
-                    return "";
-                });
-
-            regex = util.extendRegExp(startRegex, "^", "");
-
-            this.selection = this.selection.replace(regex,
-                function (match) {
-                    chunkObj.startTag = chunkObj.startTag + match;
-                    return "";
-                });
-        }
-
-        if (endRegex) {
-
-            regex = util.extendRegExp(endRegex, "", "$");
-
-            this.selection = this.selection.replace(regex,
-                function (match) {
-                    chunkObj.endTag = match + chunkObj.endTag;
-                    return "";
-                });
-
-            regex = util.extendRegExp(endRegex, "^", "");
-
-            this.after = this.after.replace(regex,
-                function (match) {
-                    chunkObj.endTag = match + chunkObj.endTag;
-                    return "";
-                });
-        }
-    };
-
-    // If remove is false, the whitespace is transferred
-    // to the before/after regions.
-    //
-    // If remove is true, the whitespace disappears.
-    Chunks.prototype.trimWhitespace = function (remove) {
-        var beforeReplacer, afterReplacer, that = this;
-        if (remove) {
-            beforeReplacer = afterReplacer = "";
-        } else {
-            beforeReplacer = function (s) { that.before += s; return ""; }
-            afterReplacer = function (s) { that.after = s + that.after; return ""; }
-        }
-
-        this.selection = this.selection.replace(/^(\s*)/, beforeReplacer).replace(/(\s*)$/, afterReplacer);
-    };
-
-
-    Chunks.prototype.skipLines = function (nLinesBefore, nLinesAfter, findExtraNewlines) {
-
-        if (nLinesBefore === undefined) {
-            nLinesBefore = 1;
-        }
-
-        if (nLinesAfter === undefined) {
-            nLinesAfter = 1;
-        }
-
-        nLinesBefore++;
-        nLinesAfter++;
-
-        var regexText;
-        var replacementText;
-
-        // chrome bug ... documented at: http://meta.stackoverflow.com/questions/63307/blockquote-glitch-in-editor-in-chrome-6-and-7/65985#65985
-        if (navigator.userAgent.match(/Chrome/)) {
-            "X".match(/()./);
-        }
-
-        this.selection = this.selection.replace(/(^\n*)/, "");
-
-        this.startTag = this.startTag + re.$1;
-
-        this.selection = this.selection.replace(/(\n*$)/, "");
-        this.endTag = this.endTag + re.$1;
-        this.startTag = this.startTag.replace(/(^\n*)/, "");
-        this.before = this.before + re.$1;
-        this.endTag = this.endTag.replace(/(\n*$)/, "");
-        this.after = this.after + re.$1;
-
-        if (this.before) {
-
-            regexText = replacementText = "";
-
-            while (nLinesBefore--) {
-                regexText += "\\n?";
-                replacementText += "\n";
-            }
-
-            if (findExtraNewlines) {
-                regexText = "\\n*";
-            }
-            this.before = this.before.replace(new re(regexText + "$", ""), replacementText);
-        }
-
-        if (this.after) {
-
-            regexText = replacementText = "";
-
-            while (nLinesAfter--) {
-                regexText += "\\n?";
-                replacementText += "\n";
-            }
-            if (findExtraNewlines) {
-                regexText = "\\n*";
-            }
-
-            this.after = this.after.replace(new re(regexText, ""), replacementText);
-        }
-    };
-
-    // end of Chunks
-
-    function firstByClass(doc, containerElement, className) {
-      var container = containerElement || doc;
-      var elements = container.getElementsByClassName(className);
-      if (elements && elements.length) {
-        return elements[0];
-      }
-    }
-
-    // A collection of the important regions on the page.
-    // Cached so we don't have to keep traversing the DOM.
-    function PanelCollection(containerElement) {
-      this.buttonBar = firstByClass(doc, containerElement, 'wmd-button-bar');
-      this.preview = firstByClass(doc, containerElement, 'wmd-preview');
-      this.input = firstByClass(doc, containerElement, 'wmd-input');
-    };
-
-    // Returns true if the DOM element is visible, false if it's hidden.
-    // Checks if display is anything other than none.
-    util.isVisible = function (elem) {
-        return window.getComputedStyle(elem, null).getPropertyValue("display") !== "none";
-    };
-
-
-    // Adds a listener callback to a DOM element which is fired on a specified
-    // event.
-    util.addEvent = function (elem, event, listener) {
-      var wrapped = function() {
-        var wrappedArgs = Array.prototype.slice.call(arguments);
-        Ember.run(function() {
-          listener.apply(this, wrappedArgs);
-        });
-      };
-      elem.addEventListener(event, wrapped, false);
-    };
-
-
-    // Removes a listener callback from a DOM element which is fired on a specified
-    // event.
-    util.removeEvent = function (elem, event, listener) {
-        elem.removeEventListener(event, listener, false);
-    };
-
-    // Converts \r\n and \r to \n.
-    util.fixEolChars = function (text) {
-        text = text.replace(/\r\n/g, "\n");
-        text = text.replace(/\r/g, "\n");
-        return text;
-    };
-
-    // Extends a regular expression.  Returns a new RegExp
-    // using pre + regex + post as the expression.
-    // Used in a few functions where we have a base
-    // expression and we want to pre- or append some
-    // conditions to it (e.g. adding "$" to the end).
-    // The flags are unchanged.
-    //
-    // regex is a RegExp, pre and post are strings.
-    util.extendRegExp = function (regex, pre, post) {
-
-        if (pre === null || pre === undefined) {
-            pre = "";
-        }
-        if (post === null || post === undefined) {
-            post = "";
-        }
-
-        var pattern = regex.toString();
-        var flags;
-
-        // Replace the flags with empty space and store them.
-        pattern = pattern.replace(/\/([gim]*)$/, function (wholeMatch, flagsPart) {
-            flags = flagsPart;
-            return "";
-        });
-
-        // Remove the slash delimiters on the regular expression.
-        pattern = pattern.replace(/(^\/|\/$)/g, "");
-        pattern = pre + pattern + post;
-
-        return new re(pattern, flags);
-    }
-
-    // UNFINISHED
-    // The assignment in the while loop makes jslint cranky.
-    // I'll change it to a better loop later.
-    position.getTop = function (elem, isInner) {
-        var result = elem.offsetTop;
-        if (!isInner) {
-            while (elem = elem.offsetParent) {
-                result += elem.offsetTop;
-            }
-        }
-        return result;
-    };
-
-    position.getHeight = function (elem) {
-        return elem.offsetHeight || elem.scrollHeight;
-    };
-
-    position.getWidth = function (elem) {
-        return elem.offsetWidth || elem.scrollWidth;
-    };
-
-    position.getPageSize = function () {
-
-        var scrollWidth, scrollHeight;
-        var innerWidth, innerHeight;
-
-        // It's not very clear which blocks work with which browsers.
-        if (self.innerHeight && self.scrollMaxY) {
-            scrollWidth = doc.body.scrollWidth;
-            scrollHeight = self.innerHeight + self.scrollMaxY;
-        }
-        else if (doc.body.scrollHeight > doc.body.offsetHeight) {
-            scrollWidth = doc.body.scrollWidth;
-            scrollHeight = doc.body.scrollHeight;
-        }
-        else {
-            scrollWidth = doc.body.offsetWidth;
-            scrollHeight = doc.body.offsetHeight;
-        }
-
-        innerWidth = self.innerWidth;
-        innerHeight = self.innerHeight;
-
-        var maxWidth = Math.max(scrollWidth, innerWidth);
-        var maxHeight = Math.max(scrollHeight, innerHeight);
-        return [maxWidth, maxHeight, innerWidth, innerHeight];
-    };
-
-    // Handles pushing and popping TextareaStates for undo/redo commands.
-    // I should rename the stack variables to list.
-    function UndoManager(callback, panels) {
-
-        var undoObj = this;
-        var undoStack = []; // A stack of undo states
-        var stackPtr = 0; // The index of the current state
-        var mode = "none";
-        var lastState; // The last state
-        var timer; // The setTimeout handle for cancelling the timer
-        var inputStateObj;
-
-        // Set the mode for later logic steps.
-        var setMode = function (newMode, noSave) {
-            if (mode != newMode) {
-                mode = newMode;
-                if (!noSave) {
-                    saveState();
-                }
-            }
-
-            if (mode != "moving") {
-                timer = setTimeout(refreshState, 1);
-            }
-            else {
-                inputStateObj = null;
-            }
-        };
-
-        var refreshState = function (isInitialState) {
-            inputStateObj = new TextareaState(panels, isInitialState);
-            timer = undefined;
-        };
-
-        this.setCommandMode = function () {
-            mode = "command";
-            saveState();
-            timer = setTimeout(refreshState, 0);
-        };
-
-        this.canUndo = function () {
-            return stackPtr > 1;
-        };
-
-        this.canRedo = function () {
-            if (undoStack[stackPtr + 1]) {
-                return true;
-            }
-            return false;
-        };
-
-        // Removes the last state and restores it.
-        this.undo = function () {
-
-            if (undoObj.canUndo()) {
-                if (lastState) {
-                    // What about setting state -1 to null or checking for undefined?
-                    lastState.restore();
-                    lastState = null;
-                }
-                else {
-                    undoStack[stackPtr] = new TextareaState(panels);
-                    undoStack[--stackPtr].restore();
-
-                    if (callback) {
-                        callback();
-                    }
-                }
-            }
-
-            mode = "none";
-            panels.input.focus();
-            refreshState();
-        };
-
-        // Redo an action.
-        this.redo = function () {
-
-            if (undoObj.canRedo()) {
-
-                undoStack[++stackPtr].restore();
-
-                if (callback) {
-                    callback();
-                }
-            }
-
-            mode = "none";
-            panels.input.focus();
-            refreshState();
-        };
-
-        // Push the input area state to the stack.
-        var saveState = function () {
-            var currState = inputStateObj || new TextareaState(panels);
-
-            if (!currState) {
-                return false;
-            }
-            if (mode == "moving") {
-                if (!lastState) {
-                    lastState = currState;
-                }
-                return;
-            }
-            if (lastState) {
-                if (undoStack[stackPtr - 1].text != lastState.text) {
-                    undoStack[stackPtr++] = lastState;
-                }
-                lastState = null;
-            }
-            undoStack[stackPtr++] = currState;
-            undoStack[stackPtr + 1] = null;
-            if (callback) {
-                callback();
-            }
-        };
-
-        var handleCtrlYZ = function (event) {
-
-            var handled = false;
-
-            if ((event.ctrlKey || event.metaKey) && !event.altKey) {
-
-                var keyCode = event.charCode;
-                var keyCodeChar = String.fromCharCode(keyCode);
-
-                switch (keyCodeChar.toLowerCase()) {
-
-                    case "y":
-                        if (!event.shiftKey) {
-                          undoObj.redo();
-                          handled = true;
-                        }
-                        break;
-
-                    case "z":
-                        if (!event.shiftKey) {
-                            undoObj.undo();
-                        }
-                        else {
-                            undoObj.redo();
-                        }
-                        handled = true;
-                        break;
-                }
-            }
-
-            if (handled) {
-                if (event.preventDefault) {
-                    event.preventDefault();
-                }
-                if (window.event) {
-                    window.event.returnValue = false;
-                }
-                return;
-            }
-        };
-
-        // Set the mode depending on what is going on in the input area.
-        var handleModeChange = function (event) {
-
-            if (!event.ctrlKey && !event.metaKey) {
-
-                var keyCode = event.keyCode;
-
-                if ((keyCode >= 33 && keyCode <= 40) || (keyCode >= 63232 && keyCode <= 63235)) {
-                    // 33 - 40: page up/dn and arrow keys
-                    // 63232 - 63235: page up/dn and arrow keys on safari
-                    setMode("moving");
-                }
-                else if (keyCode == 8 || keyCode == 46 || keyCode == 127) {
-                    // 8: backspace
-                    // 46: delete
-                    // 127: delete
-                    setMode("deleting");
-                }
-                else if (keyCode == 13) {
-                    // 13: Enter
-                    setMode("newlines");
-                }
-                else if (keyCode == 27) {
-                    // 27: escape
-                    setMode("escape");
-                }
-                else if ((keyCode < 16 || keyCode > 20) && keyCode != 91) {
-                    // 16-20 are shift, etc.
-                    // 91: left window key
-                    // I think this might be a little messed up since there are
-                    // a lot of nonprinting keys above 20.
-                    setMode("typing");
-                }
-            }
-        };
-
-        var setEventHandlers = function () {
-            util.addEvent(panels.input, "keypress", function (event) {
-                // keyCode 89: y
-                // keyCode 90: z
-                if ((event.ctrlKey || event.metaKey) && !event.altKey && (event.keyCode == 89 || event.keyCode == 90)) {
-                    event.preventDefault();
-                }
-            });
-
-            var handlePaste = function () {
-                if (inputStateObj && inputStateObj.text != panels.input.value) {
-                    if (timer == undefined) {
-                        mode = "paste";
-                        saveState();
-                        refreshState();
-                    }
-                }
-            };
-
-            util.addEvent(panels.input, "keydown", handleCtrlYZ);
-            util.addEvent(panels.input, "keydown", handleModeChange);
-            util.addEvent(panels.input, "mousedown", function () {
-                setMode("moving");
-            });
-
-            panels.input.onpaste = handlePaste;
-            panels.input.ondrop = handlePaste;
-        };
-
-        var init = function () {
-            setEventHandlers();
-            refreshState(true);
-            saveState();
-        };
-
-        init();
-    }
-
-    // end of UndoManager
-
-    // The input textarea state/contents.
-    // This is used to implement undo/redo by the undo manager.
-    function TextareaState(panels, isInitialState) {
-
-        // Aliases
-        var stateObj = this;
-        var inputArea = panels.input;
-        this.init = function () {
-            if (!util.isVisible(inputArea)) {
-                return;
-            }
-            if (!isInitialState && doc.activeElement && doc.activeElement !== inputArea) { // this happens when tabbing out of the input box
-                return;
-            }
-
-            this.setInputAreaSelectionStartEnd();
-            this.scrollTop = inputArea.scrollTop;
-            if (!this.text && inputArea.selectionStart || inputArea.selectionStart === 0) {
-                this.text = inputArea.value;
-            }
-
-        }
-
-        // Sets the selected text in the input box after we've performed an
-        // operation.
-        this.setInputAreaSelection = function () {
-
-            if (!util.isVisible(inputArea)) {
-                return;
-            }
-
-            if (inputArea.selectionStart !== undefined) {
-
-                inputArea.focus();
-                inputArea.selectionStart = stateObj.start;
-                inputArea.selectionEnd = stateObj.end;
-                inputArea.scrollTop = stateObj.scrollTop;
-            }
-            else if (doc.selection) {
-
-                if (doc.activeElement && doc.activeElement !== inputArea) {
-                    return;
-                }
-
-                inputArea.focus();
-                var range = inputArea.createTextRange();
-                range.moveStart("character", -inputArea.value.length);
-                range.moveEnd("character", -inputArea.value.length);
-                range.moveEnd("character", stateObj.end);
-                range.moveStart("character", stateObj.start);
-                range.select();
-            }
-        };
-
-        this.setInputAreaSelectionStartEnd = function () {
-
-            if (inputArea.selectionStart || inputArea.selectionStart === 0) {
-                stateObj.start = inputArea.selectionStart;
-                stateObj.end = inputArea.selectionEnd;
-            }
-            else if (doc.selection) {
-
-                stateObj.text = util.fixEolChars(inputArea.value);
-
-                var range = doc.selection.createRange();
-
-                var fixedRange = util.fixEolChars(range.text);
-                var marker = "\x07";
-                var markedRange = marker + fixedRange + marker;
-                range.text = markedRange;
-                var inputText = util.fixEolChars(inputArea.value);
-
-                range.moveStart("character", -markedRange.length);
-                range.text = fixedRange;
-
-                stateObj.start = inputText.indexOf(marker);
-                stateObj.end = inputText.lastIndexOf(marker) - marker.length;
-
-                var len = stateObj.text.length - util.fixEolChars(inputArea.value).length;
-
-                if (len) {
-                    range.moveStart("character", -fixedRange.length);
-                    while (len--) {
-                        fixedRange += "\n";
-                        stateObj.end += 1;
-                    }
-                    range.text = fixedRange;
-                }
-
-
-                this.setInputAreaSelection();
-            }
-        };
-
-        // Restore this state into the input area.
-        this.restore = function () {
-
-            if (stateObj.text != undefined && stateObj.text != inputArea.value) {
-                inputArea.value = stateObj.text;
-            }
-            this.setInputAreaSelection();
-            inputArea.scrollTop = stateObj.scrollTop;
-        };
-
-        // Gets a collection of HTML chunks from the inptut textarea.
-        this.getChunks = function () {
-
-            var chunk = new Chunks();
-            chunk.before = util.fixEolChars(stateObj.text.substring(0, stateObj.start));
-            chunk.startTag = "";
-            chunk.selection = util.fixEolChars(stateObj.text.substring(stateObj.start, stateObj.end));
-            chunk.endTag = "";
-            chunk.after = util.fixEolChars(stateObj.text.substring(stateObj.end));
-            chunk.scrollTop = stateObj.scrollTop;
-
-            return chunk;
-        };
-
-        // Sets the TextareaState properties given a chunk of markdown.
-        this.setChunks = function (chunk) {
-
-            chunk.before = chunk.before + chunk.startTag;
-            chunk.after = chunk.endTag + chunk.after;
-
-            this.start = chunk.before.length;
-            this.end = chunk.before.length + chunk.selection.length;
-            this.text = chunk.before + chunk.selection + chunk.after;
-            this.scrollTop = chunk.scrollTop;
-        };
-        this.init();
-    };
-
-    function PreviewManager(converter, panels, previewRefreshCallback) {
-
-        var managerObj = this;
-        var timeout;
-        var elapsedTime;
-        var oldInputText;
-        var maxDelay = 3000;
-        var startType = "delayed"; // The other legal value is "manual"
-
-        var paneContentHeight = function(pane) {
-          var $pane = $(pane);
-          var paneVerticalPadding = parseInt($pane.css("padding-top")) + parseInt($pane.css("padding-bottom"));
-
-          return pane.scrollHeight - paneVerticalPadding;
-        };
-
-        var syncScroll = function(isEdit) {
-          var $preview = $(panels.preview);
-          var $input = $(panels.input);
-
-          if($input.scrollTop() === 0){
-            $preview.scrollTop(0);
-            return;
-          }
-
-          if(($input.height() + $input.scrollTop() + 100) > panels.input.scrollHeight){
-            // cheat, special case for bottom
-            $preview.scrollTop(panels.preview.scrollHeight);
-            return;
-          }
-
-          var scrollPosition = $(panels.input).scrollTop();
-          var factor = panels.preview.scrollHeight / panels.input.scrollHeight;
-
-          var desired = scrollPosition * factor;
-          $preview.scrollTop(desired + 50);
-        };
-
-        var setupScrollSync = function() {
-          var sync = _.throttle(syncScroll, 20);
-          $(panels.input).scroll(function() {
-            sync();
-          });
-        };
-
-        // Adds event listeners to elements
-        var setupEvents = function (inputElem, listener) {
-            util.addEvent(inputElem, "input", listener);
-            inputElem.onpaste = listener;
-            inputElem.ondrop = listener;
-
-            util.addEvent(inputElem, "keypress", listener);
-            util.addEvent(inputElem, "keydown", listener);
-        };
-
-        var getDocScrollTop = function () {
-
-            var result = 0;
-
-            if (window.innerHeight) {
-                result = window.pageYOffset;
-            }
-            else
-                if (doc.documentElement && doc.documentElement.scrollTop) {
-                    result = doc.documentElement.scrollTop;
-                }
-                else
-                    if (doc.body) {
-                        result = doc.body.scrollTop;
-                    }
-
-            return result;
-        };
-
-        var makePreviewHtml = function () {
-
-            // If there is no registered preview panel
-            // there is nothing to do.
-            if (!panels.preview)
-                return;
-
-
-            var text = panels.input.value;
-            if (text && text == oldInputText) {
-                return; // Input text hasn't changed.
-            }
-            else {
-                oldInputText = text;
-            }
-
-            var prevTime = new Date().getTime();
-
-            var previewText;
-            previewText = converter.makeHtml(text);
-
-            // Calculate the processing time of the HTML creation.
-            // It's used as the delay time in the event listener.
-            var currTime = new Date().getTime();
-            elapsedTime = currTime - prevTime;
-
-            Ember.run(function() {
-              pushPreviewHtml(previewText);
-              syncScroll(true);
-            });
-        };
-
-        // makePreviewHtml = window.probes.measure(makePreviewHtml, {
-        //   before: function(){ window.probes.clear(); },
-        //   name: "makePreview",
-        //   after: function(p) { window.probes.clear(); console.log("Total time to preview: " + p.time); }
-        // });
-
-
-        // TODO allow us to inject this in (its our debouncer)
-        var debounce = function(func,wait,trickle) {
-          var timeout = null;
-          return function() {
-            var context = this;
-            var args = arguments;
-
-            later = function(){
-              timeout = null;
-              func.apply(context, args);
-            };
-
-            if (timeout!=null && trickle) {
-              return;
-            }
-
-            var currentWait;
-            if (typeof wait == "function") {
-              currentWait = wait();
-            } else {
-              currentWait = wait;
-            }
-
-            if (timeout) { Ember.run.cancel(timeout); }
-            timeout = Ember.run.later(later, currentWait);
-          }
-        }
-
-        makePreviewHtml = debounce(makePreviewHtml, function(){
-          return Math.min(Math.max((elapsedTime || 1) * 10, 80),1000);
-        }, true);
-
-
-        // setTimeout is already used.  Used as an event listener.
-        var applyTimeout = function () {
-
-            if (timeout) {
-                clearTimeout(timeout);
-                timeout = undefined;
-            }
-
-            if (startType !== "manual") {
-
-                var delay = 0;
-
-                if (startType === "delayed") {
-                    delay = elapsedTime;
-                }
-
-                if (delay > maxDelay) {
-                    delay = maxDelay;
-                }
-                timeout = setTimeout(makePreviewHtml, delay);
-            }
-        };
-
-        var getScaleFactor = function (panel) {
-            if (panel.scrollHeight <= panel.clientHeight) {
-                return 1;
-            }
-            return panel.scrollTop / (panel.scrollHeight - panel.clientHeight);
-        };
-
-        this.refresh = function (requiresRefresh) {
-            if (requiresRefresh) {
-                oldInputText = "";
-                makePreviewHtml();
-            }
-            else {
-                applyTimeout();
-            }
-        };
-
-        this.processingTime = function () {
-            return elapsedTime;
-        };
-
-        var isFirstTimeFilled = true;
-
-        var nonSuckyBrowserPreviewSet = function (previewText) {
-            panels.preview.innerHTML = previewText;
-        }
-
-        var previewSetter;
-
-        var previewSet = function (previewText) {
-
-            if (previewSetter)
-                return previewSetter(previewText);
-
-            nonSuckyBrowserPreviewSet(previewText);
-            previewSetter = nonSuckyBrowserPreviewSet;
-        };
-
-        var pushPreviewHtml = function (previewText) {
-
-            var emptyTop = position.getTop(panels.input) - getDocScrollTop();
-
-            if (panels.preview) {
-                previewSet(previewText);
-                previewRefreshCallback();
-            }
-
-            if (isFirstTimeFilled) {
-                isFirstTimeFilled = false;
-                return;
-            }
-
-            var fullTop = position.getTop(panels.input) - getDocScrollTop();
-
-            window.scrollBy(0, fullTop - emptyTop);
-
-        };
-
-        var init = function () {
-
-            // TODO: make option to disable. We don't need this in discourse
-            // setupEvents(panels.input, applyTimeout);
-
-            setupScrollSync();
-            makePreviewHtml();
-        };
-
-        init();
-    };
-
-    // Creates the background behind the hyperlink text entry box.
-    // And download dialog
-    // Most of this has been moved to CSS but the div creation and
-    // browser-specific hacks remain here.
-    ui.createBackground = function () {
-
-        var background = doc.createElement("div"),
-            style = background.style;
-
-        background.className = "wmd-prompt-background";
-
-        style.position = "absolute";
-        style.top = "0";
-        style.zIndex = "2000";
-        style.opacity = "0.5";
-
-        var pageSize = position.getPageSize();
-        style.height = pageSize[1] + "px";
-
-        style.left = "0";
-        style.width = "100%";
-
-        doc.body.appendChild(background);
-        return background;
-    };
-
-    // This simulates a modal dialog box and asks for the URL when you
-    // click the hyperlink or image buttons.
-    //
-    // text: The html for the input box.
-    // defaultInputText: The default value that appears in the input box.
-    // callback: The function which is executed when the prompt is dismissed, either via OK or Cancel.
-    //      It receives a single argument; either the entered text (if OK was chosen) or null (if Cancel
-    //      was chosen).
-    ui.prompt = function (text, defaultInputText, callback) {
-
-        // These variables need to be declared at this level since they are used
-        // in multiple functions.
-        var dialog;         // The dialog box.
-        var input;         // The text box where you enter the hyperlink.
-
-
-        if (defaultInputText === undefined) {
-            defaultInputText = "";
-        }
-
-        // Used as a keydown event handler. Esc dismisses the prompt.
-        // Key code 27 is ESC.
-        var checkEscape = function (key) {
-            var code = (key.charCode || key.keyCode);
-            if (code === 27) {
-                close(true);
-            }
-        };
-
-        // Dismisses the hyperlink input box.
-        // isCancel is true if we don't care about the input text.
-        // isCancel is false if we are going to keep the text.
-        var close = function (isCancel) {
-            util.removeEvent(doc.body, "keydown", checkEscape);
-            var text = input.value;
-
-            if (isCancel) {
-                text = null;
-            }
-            else {
-                // Fixes common pasting errors.
-                text = text.replace(/^http:\/\/(https?|ftp):\/\//, '$1://');
-                if (!/^(?:https?|ftp):\/\//.test(text))
-                    text = 'http://' + text;
-            }
-
-            dialog.parentNode.removeChild(dialog);
-
-            callback(text);
-            return false;
-        };
-
-
-
-        // Create the text input box form/window.
-        var createDialog = function () {
-
-            // The main dialog box.
-            dialog = doc.createElement("div");
-            dialog.className = "wmd-prompt-dialog";
-            dialog.style.padding = "10px;";
-            dialog.style.position = "fixed";
-            dialog.style.width = "400px";
-            dialog.style.zIndex = "2001";
-
-            // The dialog text.
-            var question = doc.createElement("div");
-            question.innerHTML = text;
-            question.style.padding = "5px";
-            dialog.appendChild(question);
-
-            // The web form container for the text box and buttons.
-            var form = doc.createElement("form"),
-                style = form.style;
-            form.onsubmit = function () { return close(false); };
-            style.padding = "0";
-            style.margin = "0";
-            style.cssFloat = "left";
-            style.width = "100%";
-            style.textAlign = "center";
-            style.position = "relative";
-            dialog.appendChild(form);
-
-            // The input text box
-            input = doc.createElement("input");
-            input.type = "text";
-            input.value = defaultInputText;
-            style = input.style;
-            style.display = "block";
-            style.width = "80%";
-            style.marginLeft = style.marginRight = "auto";
-            form.appendChild(input);
-
-            // The ok button
-            var okButton = doc.createElement("input");
-            okButton.type = "button";
-            okButton.onclick = function () { return close(false); };
-            okButton.value = "OK";
-            style = okButton.style;
-            style.margin = "10px";
-            style.display = "inline";
-            style.width = "7em";
-
-
-            // The cancel button
-            var cancelButton = doc.createElement("input");
-            cancelButton.type = "button";
-            cancelButton.onclick = function () { return close(true); };
-            cancelButton.value = "Cancel";
-            style = cancelButton.style;
-            style.margin = "10px";
-            style.display = "inline";
-            style.width = "7em";
-
-            form.appendChild(okButton);
-            form.appendChild(cancelButton);
-
-            util.addEvent(doc.body, "keydown", checkEscape);
-            dialog.style.top = "50%";
-            dialog.style.left = "50%";
-            dialog.style.display = "block";
-            doc.body.appendChild(dialog);
-
-            // This has to be done AFTER adding the dialog to the form if you
-            // want it to be centered.
-            dialog.style.marginTop = -(position.getHeight(dialog) / 2) + "px";
-            dialog.style.marginLeft = -(position.getWidth(dialog) / 2) + "px";
-
-        };
-
-        // Why is this in a zero-length timeout?
-        // Is it working around a browser bug?
-        setTimeout(function () {
-
-            createDialog();
-
-            var defTextLen = defaultInputText.length;
-            if (input.selectionStart !== undefined) {
-                input.selectionStart = 0;
-                input.selectionEnd = defTextLen;
-            }
-            else if (input.createTextRange) {
-                var range = input.createTextRange();
-                range.collapse(false);
-                range.moveStart("character", -defTextLen);
-                range.moveEnd("character", defTextLen);
-                range.select();
-            }
-
-            input.focus();
-        }, 0);
-    };
-
-    function UIManager(postfix, panels, undoManager, previewManager, commandManager, helpOptions, getString, options) {
-
-        var inputBox = panels.input,
-            buttons = {}; // buttons.undo, buttons.link, etc. The actual DOM elements.
-
-        makeSpritedButtonRow(options);
-
-        var keyEvent = "keydown";
-
-        var extendedEvents = [];
-
-        if(window.PagedownCustom){
-          window.PagedownCustom.appendButtons.concat(window.PagedownCustom.insertButtons).forEach(function(button){
-            if(button.shortcut){
-              extendedEvents.push([button.shortcut, button.execute]);
-            }
-          });
-        }
-
-        util.addEvent(inputBox, keyEvent, function (key) {
-
-            // Check to see if we have a button key and, if so execute the callback.
-            if ((key.ctrlKey || key.metaKey) && !key.altKey && !key.shiftKey) {
-
-                var keyCode = key.charCode || key.keyCode;
-                var keyCodeStr = String.fromCharCode(keyCode).toLowerCase();
-
-                for(var i=0; i<extendedEvents.length; i++){
-                  if(keyCodeStr===extendedEvents[i][0]){
-                    extendedEvents[i][1]();
-                  }
-                }
-
-                switch (keyCodeStr) {
-                    case "b":
-                        doClick(buttons.bold);
-                        break;
-                    case "i":
-                        doClick(buttons.italic);
-                        break;
-                    case "l":
-                        doClick(buttons.link);
-                        break;
-                    case "q":
-                        doClick(buttons.quote);
-                        break;
-                    case "k":
-                        doClick(buttons.code);
-                        break;
-                    case "g":
-                        doClick(buttons.image);
-                        break;
-                    case "o":
-                        doClick(buttons.olist);
-                        break;
-                    case "u":
-                        doClick(buttons.ulist);
-                        break;
-                    case "h":
-                        doClick(buttons.heading);
-                        break;
-                    default:
-                        return;
-                }
-
-
-                if (key.preventDefault) {
-                    key.preventDefault();
-                }
-
-                if (window.event) {
-                    window.event.returnValue = false;
-                }
-            }
-        });
-
-
-
-        // Perform the button's action.
-        function doClick(button) {
-
-            inputBox.focus();
-
-            if (button && button.textOp) {
-
-                if (undoManager) {
-                    undoManager.setCommandMode();
-                }
-
-                var state = new TextareaState(panels);
-
-                if (!state) {
-                    return;
-                }
-
-                var chunks = state.getChunks();
-
-                // Some commands launch a "modal" prompt dialog.  Javascript
-                // can't really make a modal dialog box and the WMD code
-                // will continue to execute while the dialog is displayed.
-                // This prevents the dialog pattern I'm used to and means
-                // I can't do something like this:
-                //
-                // var link = CreateLinkDialog();
-                // makeMarkdownLink(link);
-                //
-                // Instead of this straightforward method of handling a
-                // dialog I have to pass any code which would execute
-                // after the dialog is dismissed (e.g. link creation)
-                // in a function parameter.
-                //
-                // Yes this is awkward and I think it sucks, but there's
-                // no real workaround.  Only the image and link code
-                // create dialogs and require the function pointers.
-                var fixupInputArea = function () {
-
-                    inputBox.focus();
-
-                    if (chunks) {
-                        state.setChunks(chunks);
-                    }
-
-                    state.restore();
-                    previewManager.refresh();
-                };
-
-                var noCleanup = button.textOp(chunks, fixupInputArea);
-
-                if (!noCleanup) {
-                    fixupInputArea();
-                }
-
-            }
-
-            if (button.execute) {
-                button.execute(undoManager);
-            }
-        };
-
-        function setupButton(button, isEnabled) {
-
-            if (isEnabled) {
-                button.disabled = false
-
-                if (!button.isHelp) {
-                    button.onclick = function () {
-                        if (this.onmouseout) {
-                            this.onmouseout();
-                        }
-                        doClick(this);
-                        return false;
-                    }
-                }
-            }
-            else {
-                button.disabled = true
-                button.onmouseover = button.onmouseout = button.onclick = function () { };
-            }
-        }
-
-        function bindCommand(method) {
-            if (typeof PagedownCustom != "undefined" && PagedownCustom.customActions) {
-                var custom = PagedownCustom.customActions[method];
-                if (custom) {
-                    return function() {
-                        var args = Array.prototype.slice.call(arguments);
-                        args.push(commandManager[method]);
-                        return custom.apply(commandManager, args);
-                    };
-                }
-            }
-
-            if (typeof method === "string")
-                method = commandManager[method];
-            return function () { method.apply(commandManager, arguments); }
-        }
-
-        function makeSpritedButtonRow(options) {
-            options = options || {};
-
-            var buttonBar = panels.buttonBar;
-            var buttonRow = document.createElement("div");
-            buttonRow.className = 'wmd-button-row';
-            buttonRow = buttonBar.appendChild(buttonRow);
-            var xPosition = 0;
-            var makeButton = function (id, title, textOp) {
-                var button = document.createElement("button");
-                button.className = "wmd-button " + id;
-                xPosition += 25;
-                button.title = title;
-                // we really should just use jquery here
-                if (button.setAttribute) {
-                  button.setAttribute('aria-label', title);
-                }
-                if (textOp)
-                    button.textOp = textOp;
-                setupButton(button, true);
-                buttonRow.appendChild(button);
-                return button;
-            };
-
-            var makeSpacer = function (num) {
-                var spacer = document.createElement("div");
-                spacer.className = "wmd-spacer";
-                spacer.id = "wmd-spacer" + num + postfix;
-                buttonRow.appendChild(spacer);
-                xPosition += 25;
-            }
-
-            // If we have any buttons to insert, do it!
-            if (typeof PagedownCustom != "undefined") {
-                insertButtons = PagedownCustom.insertButtons
-                if (insertButtons && (insertButtons.length > 0)) {
-                    for (var i=0; i<insertButtons.length; i++) {
-                        var b = insertButtons[i];
-                        makeButton(b.id, b.description, b.execute)
-                    }
-                }
-            }
-
-            buttons.bold = makeButton("wmd-bold-button", getString("bold"), bindCommand("doBold"));
-            buttons.italic = makeButton("wmd-italic-button", getString("italic"), bindCommand("doItalic"));
-            makeSpacer(1);
-            buttons.link = makeButton("wmd-link-button", getString("link"), bindCommand(function (chunk, postProcessing) {
-                return this.doLinkOrImage(chunk, postProcessing, false);
-            }));
-            buttons.quote = makeButton("wmd-quote-button", getString("quote"), bindCommand("doBlockquote"));
-            buttons.code = makeButton("wmd-code-button", getString("code"), bindCommand("doCode"));
-            buttons.image = makeButton("wmd-image-button", getString("image"), bindCommand(function (chunk, postProcessing) {
-                return this.doLinkOrImage(chunk, postProcessing, true);
-            }));
-            makeSpacer(2);
-            buttons.olist = makeButton("wmd-olist-button", getString("olist"), bindCommand(function (chunk, postProcessing) {
-                this.doList(chunk, postProcessing, true);
-            }));
-            buttons.ulist = makeButton("wmd-ulist-button", getString("ulist"), bindCommand(function (chunk, postProcessing) {
-                this.doList(chunk, postProcessing, false);
-            }));
-            buttons.heading = makeButton("wmd-heading-button", getString("heading"), bindCommand("doHeading"));
-            buttons.hr = makeButton("wmd-hr-button", getString("hr"), bindCommand("doHorizontalRule"));
-
-            function createExtraButtons(buttons) {
-                if (buttons && (buttons.length > 0)) {
-                    for (var i=0; i< buttons.length; i++) {
-                        var b = buttons[i];
-                        makeButton(b.id, b.description, b.execute)
-                    }
-                }
-            }
-
-            // If we have any buttons to append, do it!
-            if (typeof PagedownCustom != "undefined") {
-              createExtraButtons(PagedownCustom.appendButtons);
-            }
-
-            createExtraButtons(options.appendButtons);
-
-            //makeSpacer(3);
-            //buttons.undo = makeButton("wmd-undo-button", getString("undo"), null);
-            //buttons.undo.execute = function (manager) { if (manager) manager.undo(); };
-
-            // var redoTitle = /win/.test(nav.platform.toLowerCase()) ?
-            //     getString("redo") :
-            //     getString("redomac"); // mac and other non-Windows platforms
-
-            //buttons.redo = makeButton("wmd-redo-button", redoTitle, null);
-            //buttons.redo.execute = function (manager) { if (manager) manager.redo(); };
-
-            // if (helpOptions) {
-            //     var helpButton = document.createElement("li");
-            //     var helpButtonImage = document.createElement("span");
-            //     helpButton.appendChild(helpButtonImage);
-            //     helpButton.className = "wmd-button wmd-help-button";
-            //     helpButton.id = "wmd-help-button" + postfix;
-            //     helpButton.isHelp = true;
-            //     helpButton.style.right = "0px";
-            //     helpButton.title = getString("help");
-            //     helpButton.onclick = helpOptions.handler;
-            //
-            //     setupButton(helpButton, true);
-            //     buttonRow.appendChild(helpButton);
-            //     buttons.help = helpButton;
-            // }
-
-            // setUndoRedoButtonStates();
-        }
-
-        function setUndoRedoButtonStates() {
-            if (undoManager) {
-                setupButton(buttons.undo, undoManager.canUndo());
-                setupButton(buttons.redo, undoManager.canRedo());
-            }
-        };
-
-        this.setUndoRedoButtonStates = setUndoRedoButtonStates;
-
-    }
-
-    function CommandManager(pluginHooks, getString) {
-        this.hooks = pluginHooks;
-        this.getString = getString;
-    }
-
-    var commandProto = CommandManager.prototype;
-
-    // The markdown symbols - 4 spaces = code, > = blockquote, etc.
-    commandProto.prefixes = "(?:\\s{4,}|\\s*>|\\s*-\\s+|\\s*\\d+\\.|=|\\+|-|_|\\*|#|\\s*\\[[^\n]]+\\]:)";
-
-    // Remove markdown symbols from the chunk selection.
-    commandProto.unwrap = function (chunk) {
-        var txt = new re("([^\\n])\\n(?!(\\n|" + this.prefixes + "))", "g");
-        chunk.selection = chunk.selection.replace(txt, "$1 $2");
-    };
-
-    commandProto.wrap = function (chunk, len) {
-        this.unwrap(chunk);
-        var regex = new re("(.{1," + len + "})( +|$\\n?)", "gm"),
-            that = this;
-
-        chunk.selection = chunk.selection.replace(regex, function (line, marked) {
-            if (new re("^" + that.prefixes, "").test(line)) {
-                return line;
-            }
-            return marked + "\n";
-        });
-
-        chunk.selection = chunk.selection.replace(/\s+$/, "");
-    };
-
-    commandProto.doBold = function (chunk, postProcessing) {
-        return this.doSurroundLines(chunk, postProcessing, 2, this.getString("boldexample"));
-    };
-
-    commandProto.doItalic = function (chunk, postProcessing) {
-        return this.doSurroundLines(chunk, postProcessing, 1, this.getString("italicexample"));
-    };
-
-    commandProto.doSurroundLines = function(realChunk, postProcessing, nStars, fallbackText) {
-        realChunk.trimWhitespace();
-
-        // Look for stars before and after, absorb them into the selection.
-        var starsBefore = /(\**$)/.exec(realChunk.before)[0];
-        var starsAfter = /(^\**)/.exec(realChunk.after)[0];
-
-        realChunk.before = realChunk.before.replace(/(\**$)/, "");
-        realChunk.after = realChunk.after.replace(/(^\**)/, "");
-
-        var lines = (starsBefore + realChunk.selection + starsAfter).split("\n");
-
-        // Don't show the fallback text if more than one line is selected,
-        // it's probably a break between paragraphs.
-        if (lines.length > 1) {
-            fallbackText = "";
-        }
-
-        for(var i=0; i<lines.length; i++) {
-            // Split before, selection and after up.
-            var lineMatch = lines[i].match(/^(\s*\**)(.*?)(\**\s*)$/);
-
-            var newChunk = new Chunks();
-            newChunk.before = lineMatch[1];
-            newChunk.selection = lineMatch[2];
-            newChunk.after = lineMatch[3];
-
-            this.doSurroundLine(newChunk, postProcessing, nStars, fallbackText);
-
-            if (lines.length > 1) {
-                lines[i] = newChunk.before + newChunk.selection + newChunk.after;
-            } else {
-                realChunk.startTag = newChunk.before;
-                realChunk.endTag = newChunk.after;
-                lines[i] = newChunk.selection;
-            }
-        }
-
-        realChunk.selection = lines.join("\n");
-    };
-
-    // chunk: The selected region that will be enclosed with * or **
-    // nStars: 1 for italics, 2 for bold
-    // fallbackText: If you just click the button without highlighting text, this gets inserted
-    commandProto.doSurroundLine = function (chunk, postProcessing, nStars, fallbackText) {
-        // Get rid of whitespace
-        chunk.trimWhitespace();
-
-        var minStars = Math.min(chunk.before.length, chunk.after.length);
-
-        // Remove stars if we have to since the button acts as a toggle.
-        if ((minStars >= nStars) && (minStars != 2 || nStars != 1)) {
-            chunk.before = chunk.before.replace(re("[*]{" + nStars + "}$", ""), "");
-            chunk.after = chunk.after.replace(re("^[*]{" + nStars + "}", ""), "");
-        }
-        else {
-            // In most cases, if you don't have any selected text and click the button
-            // you'll get a selected, marked up region with the default text inserted.
-            if (!chunk.selection && !chunk.after) {
-                chunk.selection = fallbackText;
-            }
-
-            // Only operate if it's not a blank line
-            if (chunk.selection) {
-                // Add the true markup.
-                var markup = nStars === 1 ? "*" : "**";
-                chunk.before = chunk.before + markup;
-                chunk.after = markup + chunk.after;
-            }
-        }
-    };
-
-    commandProto.stripLinkDefs = function (text, defsToAdd) {
-
-        text = text.replace(/^[ ]{0,3}\[(\d+)\]:[ \t]*\n?[ \t]*<?(\S+?)>?[ \t]*\n?[ \t]*(?:(\n*)["(](.+?)[")][ \t]*)?(?:\n+|$)/gm,
-            function (totalMatch, id, link, newlines, title) {
-                defsToAdd[id] = totalMatch.replace(/\s*$/, "");
-                if (newlines) {
-                    // Strip the title and return that separately.
-                    defsToAdd[id] = totalMatch.replace(/["(](.+?)[")]$/, "");
-                    return newlines + title;
-                }
-                return "";
-            });
-
-        return text;
-    };
-
-    commandProto.addLinkDef = function (chunk, linkDef) {
-
-        var refNumber = 0; // The current reference number
-        var defsToAdd = {}; //
-        // Start with a clean slate by removing all previous link definitions.
-        chunk.before = this.stripLinkDefs(chunk.before, defsToAdd);
-        chunk.selection = this.stripLinkDefs(chunk.selection, defsToAdd);
-        chunk.after = this.stripLinkDefs(chunk.after, defsToAdd);
-
-        var defs = "";
-        var regex = /(\[)((?:\[[^\]]*\]|[^\[\]])*)(\][ ]?(?:\n[ ]*)?\[)(\d+)(\])/g;
-
-        var addDefNumber = function (def) {
-            refNumber++;
-            def = def.replace(/^[ ]{0,3}\[(\d+)\]:/, "  [" + refNumber + "]:");
-            defs += "\n" + def;
-        };
-
-        // note that
-        // a) the recursive call to getLink cannot go infinite, because by definition
-        //    of regex, inner is always a proper substring of wholeMatch, and
-        // b) more than one level of nesting is neither supported by the regex
-        //    nor making a lot of sense (the only use case for nesting is a linked image)
-        var getLink = function (wholeMatch, before, inner, afterInner, id, end) {
-            inner = inner.replace(regex, getLink);
-            if (defsToAdd[id]) {
-                addDefNumber(defsToAdd[id]);
-                return before + inner + afterInner + refNumber + end;
-            }
-            return wholeMatch;
-        };
-
-        chunk.before = chunk.before.replace(regex, getLink);
-
-        if (linkDef) {
-            addDefNumber(linkDef);
-        }
-        else {
-            chunk.selection = chunk.selection.replace(regex, getLink);
-        }
-
-        var refOut = refNumber;
-
-        chunk.after = chunk.after.replace(regex, getLink);
-
-        if (chunk.after) {
-            chunk.after = chunk.after.replace(/\n*$/, "");
-        }
-        if (!chunk.after) {
-            chunk.selection = chunk.selection.replace(/\n*$/, "");
-        }
-
-        chunk.after += "\n\n" + defs;
-
-        return refOut;
-    };
-
-    // takes the line as entered into the add link/as image dialog and makes
-    // sure the URL and the optinal title are "nice".
-    function properlyEncoded(linkdef) {
-        return linkdef.replace(/^\s*(.*?)(?:\s+"(.+)")?\s*$/, function (wholematch, link, title) {
-            link = link.replace(/ /g, '%20').replace(/'/g, '%27').replace(/\(/g, '%28').replace(/\)/g, '%29');
-            if (title) {
-                title = title.trim ? title.trim() : title.replace(/^\s*/, "").replace(/\s*$/, "");
-                title = title.replace(/"/g, "quot;").replace(/\(/g, "&#40;").replace(/\)/g, "&#41;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
-            }
-            return title ? link + ' "' + title + '"' : link;
-        });
-    }
-
-    commandProto.doLinkOrImage = function (chunk, postProcessing, isImage) {
-
-        chunk.trimWhitespace();
-        chunk.findTags(/\s*!?\[/, /\][ ]?(?:\n[ ]*)?(\[.*?\])?/);
-        var background;
-
-        if (chunk.endTag.length > 1 && chunk.startTag.length > 0) {
-
-            chunk.startTag = chunk.startTag.replace(/!?\[/, "");
-            chunk.endTag = "";
-            this.addLinkDef(chunk, null);
-
-        }
-        else {
-
-            // We're moving start and end tag back into the selection, since (as we're in the else block) we're not
-            // *removing* a link, but *adding* one, so whatever findTags() found is now back to being part of the
-            // link text. linkEnteredCallback takes care of escaping any brackets.
-            chunk.selection = chunk.startTag + chunk.selection + chunk.endTag;
-            chunk.startTag = chunk.endTag = "";
-
-            if (/\n\n/.test(chunk.selection)) {
-                this.addLinkDef(chunk, null);
-                return;
-            }
-            var that = this;
-            // The function to be executed when you enter a link and press OK or Cancel.
-            // Marks up the link and adds the ref.
-            var linkEnteredCallback = function (link) {
-
-                background.parentNode.removeChild(background);
-
-                if (link !== null) {
-                    // (                          $1
-                    //     [^\\]                  anything that's not a backslash
-                    //     (?:\\\\)*              an even number (this includes zero) of backslashes
-                    // )
-                    // (?=                        followed by
-                    //     [[\]]                  an opening or closing bracket
-                    // )
-                    //
-                    // In other words, a non-escaped bracket. These have to be escaped now to make sure they
-                    // don't count as the end of the link or similar.
-                    // Note that the actual bracket has to be a lookahead, because (in case of to subsequent brackets),
-                    // the bracket in one match may be the "not a backslash" character in the next match, so it
-                    // should not be consumed by the first match.
-                    // The "prepend a space and finally remove it" steps makes sure there is a "not a backslash" at the
-                    // start of the string, so this also works if the selection begins with a bracket. We cannot solve
-                    // this by anchoring with ^, because in the case that the selection starts with two brackets, this
-                    // would mean a zero-width match at the start. Since zero-width matches advance the string position,
-                    // the first bracket could then not act as the "not a backslash" for the second.
-                    chunk.selection = (" " + chunk.selection).replace(/([^\\](?:\\\\)*)(?=[[\]])/g, "$1\\").substr(1);
-
-                    var linkDef = " [999]: " + properlyEncoded(link);
-
-                    var num = that.addLinkDef(chunk, linkDef);
-                    chunk.startTag = isImage ? "![" : "[";
-                    chunk.endTag = "][" + num + "]";
-
-                    if (!chunk.selection) {
-                        if (isImage) {
-                            chunk.selection = that.getString("imagedescription");
-                        }
-                        else {
-                            chunk.selection = that.getString("linkdescription");
-                        }
-                    }
-                }
-                postProcessing();
-            };
-
-            background = ui.createBackground();
-
-            if (isImage) {
-                if (!this.hooks.insertImageDialog(linkEnteredCallback))
-                    ui.prompt(this.getString("imagedialog"), imageDefaultText, linkEnteredCallback);
-            }
-            else {
-                ui.prompt(this.getString("linkdialog"), linkDefaultText, linkEnteredCallback);
-            }
-            return true;
-        }
-    };
-
-    commandProto.doBlockquote = function (chunk, postProcessing) {
-
-        chunk.selection = chunk.selection.replace(/^(\n*)([^\r]+?)(\n*)$/,
-            function (totalMatch, newlinesBefore, text, newlinesAfter) {
-                chunk.before += newlinesBefore;
-                chunk.after = newlinesAfter + chunk.after;
-                return text;
-            });
-
-        chunk.before = chunk.before.replace(/(>[ \t]*)$/,
-            function (totalMatch, blankLine) {
-                chunk.selection = blankLine + chunk.selection;
-                return "";
-            });
-
-        chunk.selection = chunk.selection.replace(/^(\s|>)+$/, "");
-        chunk.selection = chunk.selection || this.getString("quoteexample");
-
-        // The original code uses a regular expression to find out how much of the
-        // text *directly before* the selection already was a blockquote:
-
-        /*
-        if (chunk.before) {
-        chunk.before = chunk.before.replace(/\n?$/, "\n");
-        }
-        chunk.before = chunk.before.replace(/(((\n|^)(\n[ \t]*)*>(.+\n)*.*)+(\n[ \t]*)*$)/,
-        function (totalMatch) {
-        chunk.startTag = totalMatch;
-        return "";
-        });
-        */
-
-        // This comes down to:
-        // Go backwards as many lines a possible, such that each line
-        //  a) starts with ">", or
-        //  b) is almost empty, except for whitespace, or
-        //  c) is preceeded by an unbroken chain of non-empty lines
-        //     leading up to a line that starts with ">" and at least one more character
-        // and in addition
-        //  d) at least one line fulfills a)
-        //
-        // Since this is essentially a backwards-moving regex, it's susceptible to
-        // catstrophic backtracking and can cause the browser to hang;
-        // see e.g. http://meta.stackoverflow.com/questions/9807.
-        //
-        // Hence we replaced this by a simple state machine that just goes through the
-        // lines and checks for a), b), and c).
-
-        var match = "",
-            leftOver = "",
-            line;
-        if (chunk.before) {
-            var lines = chunk.before.replace(/\n$/, "").split("\n");
-            var inChain = false;
-            for (var i = 0; i < lines.length; i++) {
-                var good = false;
-                line = lines[i];
-                inChain = inChain && line.length > 0; // c) any non-empty line continues the chain
-                if (/^>/.test(line)) {                // a)
-                    good = true;
-                    if (!inChain && line.length > 1)  // c) any line that starts with ">" and has at least one more character starts the chain
-                        inChain = true;
-                } else if (/^[ \t]*$/.test(line)) {   // b)
-                    good = true;
-                } else {
-                    good = inChain;                   // c) the line is not empty and does not start with ">", so it matches if and only if we're in the chain
-                }
-                if (good) {
-                    match += line + "\n";
-                } else {
-                    leftOver += match + line;
-                    match = "\n";
-                }
-            }
-            if (!/(^|\n)>/.test(match)) {             // d)
-                leftOver += match;
-                match = "";
-            }
-        }
-
-        chunk.startTag = match;
-        chunk.before = leftOver;
-
-        // end of change
-
-        if (chunk.after) {
-            chunk.after = chunk.after.replace(/^\n?/, "\n");
-        }
-
-        chunk.after = chunk.after.replace(/^(((\n|^)(\n[ \t]*)*>(.+\n)*.*)+(\n[ \t]*)*)/,
-            function (totalMatch) {
-                chunk.endTag = totalMatch;
-                return "";
-            }
-        );
-
-        var replaceBlanksInTags = function (useBracket) {
-
-            var replacement = useBracket ? "> " : "";
-
-            if (chunk.startTag) {
-                chunk.startTag = chunk.startTag.replace(/\n((>|\s)*)\n$/,
-                    function (totalMatch, markdown) {
-                        return "\n" + markdown.replace(/^[ ]{0,3}>?[ \t]*$/gm, replacement) + "\n";
-                    });
-            }
-            if (chunk.endTag) {
-                chunk.endTag = chunk.endTag.replace(/^\n((>|\s)*)\n/,
-                    function (totalMatch, markdown) {
-                        return "\n" + markdown.replace(/^[ ]{0,3}>?[ \t]*$/gm, replacement) + "\n";
-                    });
-            }
-        };
-
-        if (/^(?![ ]{0,3}>)/m.test(chunk.selection)) {
-            this.wrap(chunk, SETTINGS.lineLength - 2);
-            chunk.selection = chunk.selection.replace(/^/gm, "> ");
-            replaceBlanksInTags(true);
-            chunk.skipLines();
-        } else {
-            chunk.selection = chunk.selection.replace(/^[ ]{0,3}> ?/gm, "");
-            this.unwrap(chunk);
-            replaceBlanksInTags(false);
-
-            if (!/^(\n|^)[ ]{0,3}>/.test(chunk.selection) && chunk.startTag) {
-                chunk.startTag = chunk.startTag.replace(/\n{0,2}$/, "\n\n");
-            }
-
-            if (!/(\n|^)[ ]{0,3}>.*$/.test(chunk.selection) && chunk.endTag) {
-                chunk.endTag = chunk.endTag.replace(/^\n{0,2}/, "\n\n");
-            }
-        }
-
-        chunk.selection = this.hooks.postBlockquoteCreation(chunk.selection);
-
-        if (!/\n/.test(chunk.selection)) {
-            chunk.selection = chunk.selection.replace(/^(> *)/,
-            function (wholeMatch, blanks) {
-                chunk.startTag += blanks;
-                return "";
-            });
-        }
-    };
-
-    commandProto.doCode = function (chunk, postProcessing) {
-
-        var hasTextBefore = /\S[ ]*$/.test(chunk.before);
-        var hasTextAfter = /^[ ]*\S/.test(chunk.after);
-
-        // Use 'four space' markdown if the selection is on its own
-        // line or is multiline.
-        if ((!hasTextAfter && !hasTextBefore) || /\n/.test(chunk.selection)) {
-
-            chunk.before = chunk.before.replace(/[ ]{4}$/,
-                function (totalMatch) {
-                    chunk.selection = totalMatch + chunk.selection;
-                    return "";
-                });
-
-            var nLinesBack = 1;
-            var nLinesForward = 1;
-
-            if (/(\n|^)(\t|[ ]{4,}).*\n$/.test(chunk.before)) {
-                nLinesBack = 0;
-            }
-            if (/^\n(\t|[ ]{4,})/.test(chunk.after)) {
-                nLinesForward = 0;
-            }
-
-            chunk.skipLines(nLinesBack, nLinesForward);
-
-            if (!chunk.selection) {
-                chunk.startTag = "    ";
-                chunk.selection = this.getString("codeexample");
-            }
-            else {
-                if (/^[ ]{0,3}\S/m.test(chunk.selection)) {
-                    if (/\n/.test(chunk.selection))
-                        chunk.selection = chunk.selection.replace(/^/gm, "    ");
-                    else // if it's not multiline, do not select the four added spaces; this is more consistent with the doList behavior
-                        chunk.before += "    ";
-                }
-                else {
-                    chunk.selection = chunk.selection.replace(/^(?:[ ]{4}|[ ]{0,3}\t)/gm, "");
-                }
-            }
-        }
-        else {
-            // Use backticks (`) to delimit the code block.
-
-            chunk.trimWhitespace();
-            chunk.findTags(/`/, /`/);
-
-            if (!chunk.startTag && !chunk.endTag) {
-                chunk.startTag = chunk.endTag = "`";
-                if (!chunk.selection) {
-                    chunk.selection = this.getString("codeexample");
-                }
-            }
-            else if (chunk.endTag && !chunk.startTag) {
-                chunk.before += chunk.endTag;
-                chunk.endTag = "";
-            }
-            else {
-                chunk.startTag = chunk.endTag = "";
-            }
-        }
-    };
-
-    commandProto.doList = function (chunk, postProcessing, isNumberedList) {
-
-        // These are identical except at the very beginning and end.
-        // Should probably use the regex extension function to make this clearer.
-        var previousItemsRegex = /(\n|^)(([ ]{0,3}([*+-]|\d+[.])[ \t]+.*)(\n.+|\n{2,}([*+-].*|\d+[.])[ \t]+.*|\n{2,}[ \t]+\S.*)*)\n*$/;
-        var nextItemsRegex = /^\n*(([ ]{0,3}([*+-]|\d+[.])[ \t]+.*)(\n.+|\n{2,}([*+-].*|\d+[.])[ \t]+.*|\n{2,}[ \t]+\S.*)*)\n*/;
-
-        // The default bullet is a dash but others are possible.
-        // This has nothing to do with the particular HTML bullet,
-        // it's just a markdown bullet.
-        var bullet = "-";
-
-        // The number in a numbered list.
-        var num = 1;
-
-        // Get the item prefix - e.g. " 1. " for a numbered list, " - " for a bulleted list.
-        var getItemPrefix = function () {
-            var prefix;
-            if (isNumberedList) {
-                prefix = " " + num + ". ";
-                num++;
-            }
-            else {
-                prefix = " " + bullet + " ";
-            }
-            return prefix;
-        };
-
-        // Fixes the prefixes of the other list items.
-        var getPrefixedItem = function (itemText) {
-
-            // The numbering flag is unset when called by autoindent.
-            if (isNumberedList === undefined) {
-                isNumberedList = /^\s*\d/.test(itemText);
-            }
-
-            // Renumber/bullet the list element.
-            itemText = itemText.replace(/^[ ]{0,3}([*+-]|\d+[.])\s/gm,
-                function (_) {
-                    return getItemPrefix();
-                });
-
-            return itemText;
-        };
-
-        chunk.findTags(/(\n|^)*[ ]{0,3}([*+-]|\d+[.])\s+/, null);
-
-        if (chunk.before && !/\n$/.test(chunk.before) && !/^\n/.test(chunk.startTag)) {
-            chunk.before += chunk.startTag;
-            chunk.startTag = "";
-        }
-
-        if (chunk.startTag) {
-
-            var hasDigits = /\d+[.]/.test(chunk.startTag);
-            chunk.startTag = "";
-            chunk.selection = chunk.selection.replace(/\n[ ]{4}/g, "\n");
-            this.unwrap(chunk);
-            chunk.skipLines();
-
-            if (hasDigits) {
-                // Have to renumber the bullet points if this is a numbered list.
-                chunk.after = chunk.after.replace(nextItemsRegex, getPrefixedItem);
-            }
-            if (isNumberedList == hasDigits) {
-                return;
-            }
-        }
-
-        var nLinesUp = 1;
-
-        chunk.before = chunk.before.replace(previousItemsRegex,
-            function (itemText) {
-                if (/^\s*([*+-])/.test(itemText)) {
-                    bullet = re.$1;
-                }
-                nLinesUp = /[^\n]\n\n[^\n]/.test(itemText) ? 1 : 0;
-                return getPrefixedItem(itemText);
-            });
-
-        if (!chunk.selection) {
-            chunk.selection = this.getString("litem");
-        }
-
-        var prefix = getItemPrefix();
-
-        var nLinesDown = 1;
-
-        chunk.after = chunk.after.replace(nextItemsRegex,
-            function (itemText) {
-                nLinesDown = /[^\n]\n\n[^\n]/.test(itemText) ? 1 : 0;
-                return getPrefixedItem(itemText);
-            });
-
-        chunk.trimWhitespace(true);
-        chunk.skipLines(nLinesUp, nLinesDown, true);
-        chunk.startTag = prefix;
-        var spaces = prefix.replace(/./g, " ");
-        this.wrap(chunk, SETTINGS.lineLength - spaces.length);
-        chunk.selection = chunk.selection.replace(/\n/g, "\n" + spaces);
-
-    };
-
-    commandProto.doHeading = function (chunk, postProcessing) {
-
-        // Remove leading/trailing whitespace and reduce internal spaces to single spaces.
-        chunk.selection = chunk.selection.replace(/\s+/g, " ");
-        chunk.selection = chunk.selection.replace(/(^\s+|\s+$)/g, "");
-
-        // If we clicked the button with no selected text, we just
-        // make a level 2 hash header around some default text.
-        if (!chunk.selection) {
-            chunk.startTag = "## ";
-
-            if(chunk.before === "" || !chunk.before.match(/\n$/)){
-              chunk.startTag = "\n## ";
-            }
-
-            chunk.selection = this.getString("headingexample");
-            chunk.endTag = " ##";
-
-            if(chunk.after === "" || !chunk.after.match(/^\n/)){
-              chunk.endTag = " ##\n";
-            }
-
-            return;
-        }
-
-        var headerLevel = 0;     // The existing header level of the selected text.
-
-        // Remove any existing hash heading markdown and save the header level.
-        chunk.findTags(/#+[ ]*/, /[ ]*#+/);
-        if (/#+/.test(chunk.startTag)) {
-            headerLevel = re.lastMatch.length;
-        }
-        chunk.startTag = chunk.endTag = "";
-
-        // Try to get the current header level by looking for - and = in the line
-        // below the selection.
-        chunk.findTags(null, /\s?(-+|=+)/);
-        if (/=+/.test(chunk.endTag)) {
-            headerLevel = 1;
-        }
-        if (/-+/.test(chunk.endTag)) {
-            headerLevel = 2;
-        }
-
-        // Skip to the next line so we can create the header markdown.
-        chunk.startTag = chunk.endTag = "";
-        chunk.skipLines(1, 1);
-
-        // We make a level 2 header if there is no current header.
-        // If there is a header level, we substract one from the header level.
-        // If it's already a level 1 header, it's removed.
-        var headerLevelToCreate = headerLevel == 0 ? 2 : headerLevel - 1;
-
-        if (headerLevelToCreate > 0) {
-
-            // The button only creates level 1 and 2 underline headers.
-            // Why not have it iterate over hash header levels?  Wouldn't that be easier and cleaner?
-            var headerChar = headerLevelToCreate >= 2 ? "-" : "=";
-            var len = chunk.selection.length;
-            if (len > SETTINGS.lineLength) {
-                len = SETTINGS.lineLength;
-            }
-            chunk.endTag = "\n";
-            while (len--) {
-                chunk.endTag += headerChar;
-            }
-        }
-    };
-
-    commandProto.doHorizontalRule = function (chunk, postProcessing) {
-        chunk.startTag = "----------\n";
-        chunk.selection = "";
-        chunk.skipLines(2, 1, true);
-    }
-
-
-})();
diff --git a/app/assets/javascripts/discourse/lib/markdown.js b/app/assets/javascripts/discourse/lib/markdown.js
index 888f282d182..82208382cf5 100644
--- a/app/assets/javascripts/discourse/lib/markdown.js
+++ b/app/assets/javascripts/discourse/lib/markdown.js
@@ -1,5 +1,3 @@
-/*global Markdown, console */
-
 /**
   Contains methods to help us with markdown formatting.
 
@@ -152,58 +150,6 @@ Discourse.Markdown = {
     return this.markdownConverter(opts).makeHtml(raw);
   },
 
-  createEditor: function(options) {
-    options = options || {};
-
-    // By default we always sanitize content in the editor
-    options.sanitize = true;
-
-    var markdownConverter = Discourse.Markdown.markdownConverter(options);
-
-    var editorOptions = {
-      containerElement: options.containerElement,
-      strings: {
-        bold: I18n.t("composer.bold_title") + " <strong> Ctrl+B",
-        boldexample: I18n.t("composer.bold_text"),
-
-        italic: I18n.t("composer.italic_title") + " <em> Ctrl+I",
-        italicexample: I18n.t("composer.italic_text"),
-
-        link: I18n.t("composer.link_title") + " <a> Ctrl+L",
-        linkdescription: I18n.t("composer.link_description"),
-        linkdialog: "<p><b>" + I18n.t("composer.link_dialog_title") + "</b></p><p>http://example.com/ \"" +
-            I18n.t("composer.link_optional_text") + "\"</p>",
-
-        quote: I18n.t("composer.quote_title") + " <blockquote> Ctrl+Q",
-        quoteexample: I18n.t("composer.quote_text"),
-
-        code: I18n.t("composer.code_title") + " <pre><code> Ctrl+K",
-        codeexample: I18n.t("composer.code_text"),
-
-        image: I18n.t("composer.upload_title") + " - Ctrl+G",
-        imagedescription: I18n.t("composer.upload_description"),
-
-        olist: I18n.t("composer.olist_title") + " <ol> Ctrl+O",
-        ulist: I18n.t("composer.ulist_title") + " <ul> Ctrl+U",
-        litem: I18n.t("composer.list_item"),
-
-        heading: I18n.t("composer.heading_title") + " <h1>/<h2> Ctrl+H",
-        headingexample: I18n.t("composer.heading_text"),
-
-        hr: I18n.t("composer.hr_title") + " <hr> Ctrl+R",
-
-        undo: I18n.t("composer.undo_title") + " - Ctrl+Z",
-        redo: I18n.t("composer.redo_title") + " - Ctrl+Y",
-        redomac: I18n.t("composer.redo_title") + " - Ctrl+Shift+Z",
-
-        help: I18n.t("composer.help")
-      },
-      appendButtons: options.appendButtons
-    };
-
-    return new Markdown.Editor(markdownConverter, undefined, editorOptions);
-  },
-
   /**
     Checks to see if a URL is allowed in the cooked content
 
diff --git a/app/assets/javascripts/discourse/lib/show-modal.js.es6 b/app/assets/javascripts/discourse/lib/show-modal.js.es6
index 01cc0240213..485638cc476 100644
--- a/app/assets/javascripts/discourse/lib/show-modal.js.es6
+++ b/app/assets/javascripts/discourse/lib/show-modal.js.es6
@@ -1,4 +1,4 @@
-export default (name, opts) => {
+export default function(name, opts) {
   opts = opts || {};
 
   if (opts.__type) {
diff --git a/app/assets/javascripts/discourse/lib/utilities.js b/app/assets/javascripts/discourse/lib/utilities.js
index f398e791033..f01cec58164 100644
--- a/app/assets/javascripts/discourse/lib/utilities.js
+++ b/app/assets/javascripts/discourse/lib/utilities.js
@@ -215,10 +215,6 @@ Discourse.Utilities = {
     }
   },
 
-  getUploadPlaceholder: function() {
-    return "[" + I18n.t("uploading") + "]() ";
-  },
-
   isAnImage: function(path) {
     return (/\.(png|jpe?g|gif|bmp|tiff?|svg|webp)$/i).test(path);
   },
diff --git a/app/assets/javascripts/discourse/models/composer.js.es6 b/app/assets/javascripts/discourse/models/composer.js.es6
index f566ef943a6..352c6f1989f 100644
--- a/app/assets/javascripts/discourse/models/composer.js.es6
+++ b/app/assets/javascripts/discourse/models/composer.js.es6
@@ -173,11 +173,6 @@ const Composer = RestModel.extend({
 
   }.property('action', 'post', 'topic', 'topic.title'),
 
-  toggleText: function() {
-    return this.get('showPreview') ? I18n.t('composer.hide_preview') : I18n.t('composer.show_preview');
-  }.property('showPreview'),
-
-  hidePreview: Em.computed.not('showPreview'),
 
   // whether to disable the post button
   cantSubmitPost: function() {
@@ -311,8 +306,6 @@ const Composer = RestModel.extend({
   }.property('reply'),
 
   _setupComposer: function() {
-    const val = (Discourse.Mobile.mobileView ? false : (this.keyValueStore.get('composer.showPreview') || 'true'));
-    this.set('showPreview', val === 'true');
     this.set('archetypeId', this.site.get('default_archetype'));
   }.on('init'),
 
@@ -364,11 +357,6 @@ const Composer = RestModel.extend({
     return before.length + text.length;
   },
 
-  togglePreview() {
-    this.toggleProperty('showPreview');
-    this.keyValueStore.set({ key: 'composer.showPreview', value: this.get('showPreview') });
-  },
-
   applyTopicTemplate(oldCategoryId, categoryId) {
     if (this.get('action') !== CREATE_TOPIC) { return; }
     let reply = this.get('reply');
@@ -680,7 +668,7 @@ const Composer = RestModel.extend({
   },
 
   getCookedHtml() {
-    return $('#reply-control .wmd-preview').html().replace(/<span class="marker"><\/span>/g, '');
+    return $('#reply-control .d-editor-preview').html().replace(/<span class="marker"><\/span>/g, '');
   },
 
   saveDraft() {
diff --git a/app/assets/javascripts/discourse/pre-initializers/sniff-capabilities.js.es6 b/app/assets/javascripts/discourse/pre-initializers/sniff-capabilities.js.es6
index d728c93f37d..382d7749da0 100644
--- a/app/assets/javascripts/discourse/pre-initializers/sniff-capabilities.js.es6
+++ b/app/assets/javascripts/discourse/pre-initializers/sniff-capabilities.js.es6
@@ -6,24 +6,29 @@ export default {
   initialize(container, application) {
     const $html = $('html'),
           touch = $html.hasClass('touch') || (Modernizr.prefixed("MaxTouchPoints", navigator) > 1),
-          caps = Ember.Object.create();
+          caps = {touch};
 
     // Store the touch ability in our capabilities object
-    caps.set('touch', touch);
     $html.addClass(touch ? 'discourse-touch' : 'discourse-no-touch');
 
     // Detect Devices
     if (navigator) {
       const ua = navigator.userAgent;
       if (ua) {
-        caps.set('android', ua.indexOf('Android') !== -1);
-        caps.set('winphone', ua.indexOf('Windows Phone') !== -1);
+        caps.isAndroid = ua.indexOf('Android') !== -1;
+        caps.isWinphone = ua.indexOf('Windows Phone') !== -1;
+
+        caps.isOpera = !!window.opera || ua.indexOf(' OPR/') >= 0;
+        caps.isFirefox =  typeof InstallTrigger !== 'undefined';
+        caps.isSafari = Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0;
+        caps.isChrome = !!window.chrome && !caps.isOpera;
+        caps.canPasteImages = caps.isChrome || caps.isFirefox;
       }
     }
 
     // We consider high res a device with 1280 horizontal pixels. High DPI tablets like
     // iPads should report as 1024.
-    caps.set('highRes', window.screen.width >= 1280);
+    caps.highRes = window.screen.width >= 1280;
 
     // Inject it
     application.register('capabilities:main', caps, { instantiate: false });
diff --git a/app/assets/javascripts/discourse/routes/application.js.es6 b/app/assets/javascripts/discourse/routes/application.js.es6
index e3280b18206..7175aa86437 100644
--- a/app/assets/javascripts/discourse/routes/application.js.es6
+++ b/app/assets/javascripts/discourse/routes/application.js.es6
@@ -89,13 +89,11 @@ const ApplicationRoute = Discourse.Route.extend(OpenComposer, {
     },
 
     showNotActivated(props) {
-      const controller = showModal('not-activated', {title: 'log_in' });
-      controller.setProperties(props);
+      showModal('not-activated', {title: 'log_in' }).setProperties(props);
     },
 
-    showUploadSelector(composerView) {
-      showModal('uploadSelector');
-      this.controllerFor('upload-selector').setProperties({ composerView: composerView });
+    showUploadSelector(toolbarEvent) {
+      showModal('uploadSelector').setProperties({ toolbarEvent, imageUrl: null, imageLink: null });
     },
 
     showKeyboardShortcutsHelp() {
diff --git a/app/assets/javascripts/discourse/templates/components/composer-editor.hbs b/app/assets/javascripts/discourse/templates/components/composer-editor.hbs
new file mode 100644
index 00000000000..23acc3df15c
--- /dev/null
+++ b/app/assets/javascripts/discourse/templates/components/composer-editor.hbs
@@ -0,0 +1,30 @@
+{{d-editor tabindex="4"
+           value=composer.reply
+           placeholder="composer.reply_placeholder"
+           previewUpdated="previewUpdated"
+           markdownOptions=markdownOptions
+           extraButtons="extraButtons"
+           importQuote="importQuote"
+           showOptions="showOptions"
+           showUploadModal="showUploadModal"
+           validation=validation
+           loading=composer.loading}}
+
+<div class="composer-bottom-right">
+  {{#if site.mobileView}}
+    <input type="file" id="mobile-uploader" />
+    <a class="mobile-file-upload {{if isUploading 'hidden'}}">{{i18n 'upload'}}</a>
+  {{else}}
+    <a href {{action "togglePreview"}} class='toggle-preview'>{{{toggleText}}}</a>
+  {{/if}}
+  {{#if isUploading}}
+    <div id="file-uploading">
+      {{loading-spinner size="small"}} {{i18n 'upload_selector.uploading'}}
+      {{uploadProgress}}%
+      <a href id="cancel-file-upload" {{action "cancelUpload"}}>{{fa-icon "times"}}</a>
+    </div>
+  {{/if}}
+  <div id='draft-status' class="{{if isUploading 'hidden'}}">
+    {{draftStatus}}
+  </div>
+</div>
diff --git a/app/assets/javascripts/discourse/templates/components/composer-title.hbs b/app/assets/javascripts/discourse/templates/components/composer-title.hbs
new file mode 100644
index 00000000000..1294aa29661
--- /dev/null
+++ b/app/assets/javascripts/discourse/templates/components/composer-title.hbs
@@ -0,0 +1,8 @@
+{{text-field value=composer.title
+             tabindex="2"
+             id="reply-title"
+             maxLength=siteSettings.max_topic_title_length
+             placeholderKey="composer.title_placeholder"
+             disabled=composer.loading}}
+
+{{popup-input-tip validation=validation}}
diff --git a/app/assets/javascripts/discourse/templates/components/d-editor.hbs b/app/assets/javascripts/discourse/templates/components/d-editor.hbs
index 5375d94c188..64ea8909867 100644
--- a/app/assets/javascripts/discourse/templates/components/d-editor.hbs
+++ b/app/assets/javascripts/discourse/templates/components/d-editor.hbs
@@ -17,10 +17,17 @@
       {{/unless}}
     {{/each}}
   </div>
+  <div class='d-editor-preview-header'></div>
 
-  {{textarea value=value class="d-editor-input"}}
+  <div class="d-editor-textarea-wrapper">
+    {{conditional-loading-spinner condition=loading}}
+    {{textarea tabindex=tabindex value=value class="d-editor-input" placeholder=placeholderTranslated}}
+    {{popup-input-tip validation=validation}}
+  </div>
 
-  <div class="d-editor-preview {{unless preview 'hidden'}}">
-    {{{preview}}}
+  <div class="d-editor-preview-wrapper">
+    <div class="d-editor-preview">
+      {{{preview}}}
+    </div>
   </div>
 </div>
diff --git a/app/assets/javascripts/discourse/templates/composer.hbs b/app/assets/javascripts/discourse/templates/composer.hbs
index 1ddddf852b9..aac6c07f10a 100644
--- a/app/assets/javascripts/discourse/templates/composer.hbs
+++ b/app/assets/javascripts/discourse/templates/composer.hbs
@@ -56,15 +56,12 @@
                 {{/if}}
               {{/if}}
 
-              <div class="title-input">
-                {{text-field value=model.title tabindex="2" id="reply-title" maxLength=maxTitleLength placeholderKey="composer.title_placeholder"}}
-                {{popup-input-tip validation=view.titleValidation shownAt=view.showTitleTip}}
-              </div>
+              {{composer-title composer=model lastValidatedAt=lastValidatedAt}}
 
               {{#if model.showCategoryChooser}}
                 <div class="category-input">
                   {{category-chooser valueAttribute="id" value=model.categoryId scopedCategoryId=scopedCategoryId tabindex="3"}}
-                  {{popup-input-tip validation=view.categoryValidation shownAt=view.showCategoryTip}}
+                  {{popup-input-tip validation=categoryValidation}}
                 </div>
                 {{#if model.archetype.hasOptions}}
                   <button class='btn' {{action "showOptions"}}>{{i18n 'topic.options'}}</button>
@@ -77,35 +74,15 @@
           {{plugin-outlet "composer-fields"}}
         </div>
 
-        <div class='wmd-controls'>
-          <div class='textarea-wrapper'>
-            <div class='wmd-button-bar'></div>
-            <div class='wmd-preview-scroller'></div>
-            {{conditional-loading-spinner condition=model.loading}}
-            {{composer-text-area tabindex="4" value=model.reply}}
-            {{popup-input-tip validation=view.replyValidation shownAt=view.showReplyTip}}
-          </div>
-          <!-- keep the classes here in sync with post.hbs -->
-          <div class='preview-wrapper regular'>
-            <div class="wmd-preview cooked {{if model.hidePreview 'hidden'}}"></div>
-          </div>
-          <div class="composer-bottom-right">
-            {{#if site.mobileView}}
-              <input type="file" id="mobile-uploader" />
-              <a class="mobile-file-upload {{if view.isUploading 'hidden'}}">{{i18n 'upload'}}</a>
-            {{else}}
-              <a href {{action "togglePreview"}} class='toggle-preview'>{{{model.toggleText}}}</a>
-            {{/if}}
-            {{#if view.isUploading}}
-              <div id="file-uploading">
-                {{loading-spinner size="small"}} {{i18n 'upload_selector.uploading'}} {{view.uploadProgress}}% <a id="cancel-file-upload">{{fa-icon "times"}}</a>
-              </div>
-            {{/if}}
-            <div id='draft-status' class="{{if view.isUploading 'hidden'}}">
-              {{model.draftStatus}}
-            </div>
-          </div>
-        </div>
+        {{composer-editor topic=topic
+                          composer=model
+                          lastValidatedAt=lastValidatedAt
+                          canWhisper=canWhisper
+                          draftStatus=model.draftStatus
+                          isUploading=isUploading
+                          importQuote="importQuote"
+                          showOptions="showOptions"
+                          showUploadSelector="showUploadSelector"}}
 
         {{#if currentUser}}
           <div class='submit-panel'>
diff --git a/app/assets/javascripts/discourse/templates/modal/upload_selector.hbs b/app/assets/javascripts/discourse/templates/modal/upload-selector.hbs
similarity index 63%
rename from app/assets/javascripts/discourse/templates/modal/upload_selector.hbs
rename to app/assets/javascripts/discourse/templates/modal/upload-selector.hbs
index 254e02648b1..943ad5004a1 100644
--- a/app/assets/javascripts/discourse/templates/modal/upload_selector.hbs
+++ b/app/assets/javascripts/discourse/templates/modal/upload-selector.hbs
@@ -5,7 +5,7 @@
     {{#if local}}
       <div class="inputs">
         <input type="file" id="filename-input" multiple><br>
-        <span class="description">{{unbound view.tip}}</span>
+        <span class="description">{{tip}}</span>
       </div>
     {{/if}}
   </div>
@@ -14,31 +14,34 @@
     <label class="radio" for="remote">{{i18n 'upload_selector.from_the_web'}}</label>
     {{#if remote}}
       <div class="inputs">
-        <input type="text" id="fileurl-input" placeholder="http://example.com/image.png"><br>
-        <span class="description">{{unbound view.tip}}</span>
+        {{input value=imageUrl placeholder="http://example.com/image.png"}}
+        <span class="description">{{tip}}</span>
       </div>
     {{/if}}
   </div>
   {{#if showMore}}
     <div class="radios">
       <div class="inputs">
-        <input type="text" id="link-input" placeholder="http://example.com"><br>
+        {{input value=imageLink laceholder="http://example.com"}}
         <span class="description">{{i18n 'upload_selector.image_link'}}</span>
       </div>
     </div>
   {{/if}}
   <div class="radios">
     <div class="inputs">
-      <p class="hint">{{unbound view.hint}}</p>
+      <p class="hint">
+        {{#if capabilities.canPasteImages}}
+          {{i18n 'upload_selector.hint'}}
+        {{else}}
+          {{i18n 'upload_selector.hint_for_supported_browsers'}}
+        {{/if}}
+      </p>
     </div>
   </div>
 </div>
 
 <div class="modal-footer">
-  <button class="btn btn-primary" {{action "upload" target="view"}}>
-    <span class='add-upload'><i {{bind-attr class=":fa view.uploadIcon"}}></i></span>
-    {{i18n 'upload'}}
-  </button>
-  <a {{action "closeModal"}}>{{i18n 'cancel'}}</a>
+  {{d-button action="upload" class='btn-primary' icon=uploadIcon label='upload'}}
+  <a href {{action "closeModal"}}>{{i18n 'cancel'}}</a>
   {{#if remote}}<a {{action "toggleShowMore"}} class="pull-right">{{i18n 'show_more'}}</a>{{/if}}
 </div>
diff --git a/app/assets/javascripts/discourse/templates/topic.hbs b/app/assets/javascripts/discourse/templates/topic.hbs
index a93086ad187..ac3a9a9bc91 100644
--- a/app/assets/javascripts/discourse/templates/topic.hbs
+++ b/app/assets/javascripts/discourse/templates/topic.hbs
@@ -15,9 +15,9 @@
           {{#if editingTopic}}
             {{#if model.isPrivateMessage}}
               <span class="private-message-glyph">{{fa-icon "envelope"}}</span>
-              {{autofocus-text-field id="edit-title" value=buffered.title maxLength=maxTitleLength}}
+              {{autofocus-text-field id="edit-title" value=buffered.title maxlength=siteSettings.max_topic_title_length}}
             {{else}}
-              {{autofocus-text-field id="edit-title" value=buffered.title maxLength=maxTitleLength}}
+              {{autofocus-text-field id="edit-title" value=buffered.title maxlength=siteSettings.max_topic_title_length}}
               <br>
               {{category-chooser valueAttribute="id" value=buffered.category_id source=buffered.category_id}}
             {{/if}}
diff --git a/app/assets/javascripts/discourse/views/composer.js.es6 b/app/assets/javascripts/discourse/views/composer.js.es6
index a46a9e1e8ab..54da8125b9c 100644
--- a/app/assets/javascripts/discourse/views/composer.js.es6
+++ b/app/assets/javascripts/discourse/views/composer.js.es6
@@ -1,57 +1,25 @@
-import userSearch from 'discourse/lib/user-search';
 import afterTransition from 'discourse/lib/after-transition';
-import loadScript from 'discourse/lib/load-script';
 import positioningWorkaround from 'discourse/lib/safari-hacks';
-import debounce from 'discourse/lib/debounce';
-import { linkSeenMentions, fetchUnseenMentions } from 'discourse/lib/link-mentions';
 import { headerHeight } from 'discourse/views/header';
-import { showSelector } from 'discourse/lib/emoji/emoji-toolbar';
+import { default as computed, on, observes } from 'ember-addons/ember-computed-decorators';
+import Composer from 'discourse/models/composer';
 
 const ComposerView = Ember.View.extend(Ember.Evented, {
   _lastKeyTimeout: null,
-  templateName: 'composer',
   elementId: 'reply-control',
-  classNameBindings: ['model.creatingPrivateMessage:private-message',
+  classNameBindings: ['composer.creatingPrivateMessage:private-message',
                       'composeState',
-                      'model.loading',
-                      'model.canEditTitle:edit-title',
-                      'postMade',
-                      'model.creatingTopic:topic',
-                      'model.showPreview',
-                      'model.hidePreview'],
+                      'composer.loading',
+                      'composer.canEditTitle:edit-title',
+                      'composer.createdPost:created-post',
+                      'composer.creatingTopic:topic'],
 
-  model: Em.computed.alias('controller.model'),
+  composer: Em.computed.alias('controller.model'),
 
-  // This is just in case something still references content. Can probably be removed
-  content: Em.computed.alias('model'),
-
-  composeState: function() {
-    return this.get('model.composeState') || Discourse.Composer.CLOSED;
-  }.property('model.composeState'),
-
-  // Disable fields when we're loading
-  loadingChanged: function() {
-    if (this.get('loading')) {
-      this.$('.wmd-input, #reply-title').prop('disabled', 'disabled');
-    } else {
-      this.$('.wmd-input, #reply-title').prop('disabled', '');
-    }
-  }.observes('loading'),
-
-  postMade: function() {
-    return !Ember.isEmpty(this.get('model.createdPost')) ? 'created-post' : null;
-  }.property('model.createdPost'),
-
-  refreshPreview: debounce(function() {
-    if (this.editor) {
-      this.editor.refreshPreview();
-    }
-  }, 30),
-
-  observeReplyChanges: function() {
-    if (this.get('model.hidePreview')) return;
-    Ember.run.scheduleOnce('afterRender', this, 'refreshPreview');
-  }.observes('model.reply', 'model.hidePreview'),
+  @computed('composer.composeState')
+  composeState(composeState) {
+    return composeState || Composer.CLOSED;
+  },
 
   movePanels(sizePx) {
     $('#main-outlet').css('padding-bottom', sizePx);
@@ -60,44 +28,41 @@ const ComposerView = Ember.View.extend(Ember.Evented, {
     this.appEvents.trigger("composer:resized");
   },
 
-  resize: function() {
+  @observes('composeState', 'composer.action')
+  resize() {
     Ember.run.scheduleOnce('afterRender', () => {
-      let h = $('#reply-control').height() || 0;
+      const h = $('#reply-control').height() || 0;
       this.movePanels(h + "px");
 
       // Figure out the size of the fields
       const $fields = this.$('.composer-fields');
-      let pos = $fields.position();
-
-      if (pos) {
-        this.$('.wmd-controls').css('top', $fields.height() + pos.top + 5);
+      const fieldPos = $fields.position();
+      if (fieldPos) {
+        this.$('.wmd-controls').css('top', $fields.height() + fieldPos.top + 5);
       }
 
       // get the submit panel height
-      pos = this.$('.submit-panel').position();
-      if (pos) {
-        this.$('.wmd-controls').css('bottom', h - pos.top + 7);
+      const submitPos = this.$('.submit-panel').position();
+      if (submitPos) {
+        this.$('.wmd-controls').css('bottom', h - submitPos.top + 7);
       }
-
     });
-  }.observes('model.composeState', 'model.action'),
+  },
 
   keyUp() {
     const controller = this.get('controller');
     controller.checkReplyLength();
 
-    this.get('controller.model').typing();
+    this.get('composer').typing();
 
     const lastKeyUp = new Date();
-    this.set('lastKeyUp', lastKeyUp);
+    this._lastKeyUp = lastKeyUp;
 
     // One second from now, check to see if the last key was hit when
     // we recorded it. If it was, the user paused typing.
-    const self = this;
-
     Ember.run.cancel(this._lastKeyTimeout);
-    this._lastKeyTimeout = Ember.run.later(function() {
-      if (lastKeyUp !== self.get('lastKeyUp')) return;
+    this._lastKeyTimeout = Ember.run.later(() => {
+      if (lastKeyUp !== this._lastKeyUp) { return; }
 
       // Search for similar topics if the user pauses typing
       controller.findSimilarTopics();
@@ -106,7 +71,6 @@ const ComposerView = Ember.View.extend(Ember.Evented, {
 
   keyDown(e) {
     if (e.which === 27) {
-      // ESC
       this.get('controller').send('hitEsc');
       return false;
     } else if (e.which === 13 && (e.ctrlKey || e.metaKey)) {
@@ -116,557 +80,25 @@ const ComposerView = Ember.View.extend(Ember.Evented, {
     }
   },
 
-  _enableResizing: function() {
+  @on('didInsertElement')
+  _enableResizing() {
     const $replyControl = $('#reply-control');
-
-    const runResize = () => {
-      Ember.run(() => this.resize());
-    };
+    const resize = () => Ember.run(() => this.resize());
 
     $replyControl.DivResizer({
-      maxHeight(winHeight) {
-        return winHeight - headerHeight();
-      },
-      resize: runResize,
-      onDrag: (sizePx) => this.movePanels(sizePx)
+      resize,
+      maxHeight: winHeight => winHeight - headerHeight(),
+      onDrag: sizePx => this.movePanels(sizePx)
     });
 
-    afterTransition($replyControl, runResize);
-    this.set('controller.view', this);
-
+    afterTransition($replyControl, resize);
     positioningWorkaround(this.$());
-  }.on('didInsertElement'),
-
-  _unlinkView: function() {
-    this.set('controller.view', null);
-  }.on('willDestroyElement'),
+  },
 
   click() {
     this.get('controller').send('openIfDraft');
-  },
-
-  // Called after the preview renders. Debounced for performance
-  afterRender() {
-    if (this._state !== "inDOM") { return; }
-
-    const $wmdPreview = this.$('.wmd-preview');
-    if ($wmdPreview.length === 0) return;
-
-    const post = this.get('model.post');
-    let refresh = false;
-
-    // If we are editing a post, we'll refresh its contents once. This is a feature that
-    // allows a user to refresh its contents once.
-    if (post && !post.get('refreshedPost')) {
-      refresh = true;
-      post.set('refreshedPost', true);
-    }
-
-    // Load the post processing effects
-    $('a.onebox', $wmdPreview).each(function(i, e) {
-      Discourse.Onebox.load(e, refresh);
-    });
-
-    const unseen = linkSeenMentions($wmdPreview, this.siteSettings);
-    if (unseen.length) {
-      Ember.run.debounce(this, this._renderUnseen, $wmdPreview, unseen, 500);
-    }
-
-    this.trigger('previewRefreshed', $wmdPreview);
-  },
-
-  _renderUnseen: function($wmdPreview, unseen) {
-    fetchUnseenMentions($wmdPreview, unseen, this.siteSettings).then(() => {
-      linkSeenMentions($wmdPreview, this.siteSettings);
-      this.trigger('previewRefreshed', $wmdPreview);
-    });
-  },
-
-  _applyEmojiAutocomplete() {
-    if (!this.siteSettings.enable_emoji) { return; }
-
-    const container = this.container;
-    const template = container.lookup('template:emoji-selector-autocomplete.raw');
-    const controller = this.get('controller');
-
-    this.$('.wmd-input').autocomplete({
-      template: template,
-      key: ":",
-
-      transformComplete(v) {
-        if (v.code) {
-          return `${v.code}:`;
-        } else {
-          showSelector({
-            container,
-            onSelect(title) {
-              controller.appendTextAtCursor(title + ':', {space: false});
-            }
-          });
-          return "";
-        }
-      },
-
-      dataSource(term) {
-        return new Ember.RSVP.Promise(resolve => {
-          const full = `:${term}`;
-          term = term.toLowerCase();
-
-          if (term === "") {
-            return resolve(["smile", "smiley", "wink", "sunny", "blush"]);
-          }
-
-          if (Discourse.Emoji.translations[full]) {
-            return resolve([Discourse.Emoji.translations[full]]);
-          }
-
-          const options = Discourse.Emoji.search(term, {maxResults: 5});
-
-          return resolve(options);
-        }).then(list => list.map(code => {
-          return {code, src: Discourse.Emoji.urlFor(code)};
-        })).then(list => {
-          if (list.length) {
-            list.push({ label: I18n.t("composer.more_emoji") });
-          }
-          return list;
-        });
-      }
-    });
-  },
-
-  initEditor() {
-    // not quite right, need a callback to pass in, meaning this gets called once,
-    // but if you start replying to another topic it will get the avatars wrong
-    let $wmdInput;
-    const self = this;
-    const controller = this.get('controller');
-
-    this.wmdInput = $wmdInput = this.$('.wmd-input');
-    if ($wmdInput.length === 0 || $wmdInput.data('init') === true) return;
-
-    loadScript('defer/html-sanitizer-bundle');
-    ComposerView.trigger("initWmdEditor");
-    this._applyEmojiAutocomplete();
-
-    const template = this.container.lookup('template:user-selector-autocomplete.raw');
-    $wmdInput.data('init', true);
-    $wmdInput.autocomplete({
-      template: template,
-      dataSource(term) {
-        return userSearch({
-          term: term,
-          topicId: controller.get('controllers.topic.model.id'),
-          includeGroups: true
-        });
-      },
-      key: "@",
-      transformComplete(v) {
-        return v.username ? v.username : v.usernames.join(", @");
-      }
-    });
-
-
-    const options = {
-      containerElement: this.element,
-      lookupAvatarByPostNumber(postNumber, topicId) {
-        const posts = controller.get('controllers.topic.model.postStream.posts');
-        if (posts && topicId === controller.get('controllers.topic.model.id')) {
-          const quotedPost = posts.findProperty("post_number", postNumber);
-          if (quotedPost) {
-            return Discourse.Utilities.tinyAvatar(quotedPost.get('avatar_template'));
-          }
-        }
-      }
-    };
-
-    const showOptions = controller.get('canWhisper');
-    if (showOptions) {
-      options.appendButtons = [{
-        id: 'wmd-composer-options',
-        description: I18n.t("composer.options"),
-        execute() {
-          const toolbarPos = self.$('.wmd-controls').position();
-          const pos = self.$('.wmd-composer-options').position();
-
-          const location = {
-            position: "absolute",
-            left: toolbarPos.left + pos.left,
-            top: toolbarPos.top + pos.top,
-          };
-          controller.send('showOptions', location);
-        }
-      }];
-    }
-
-    this.editor = Discourse.Markdown.createEditor(options);
-
-    // HACK to change the upload icon of the composer's toolbar
-    if (!Discourse.Utilities.allowsAttachments()) {
-      Em.run.scheduleOnce("afterRender", function() {
-        $("#wmd-image-button").addClass("image-only");
-      });
-    }
-
-    this.editor.hooks.insertImageDialog = function(callback) {
-      callback(null);
-      controller.send('showUploadSelector', self);
-      return true;
-    };
-
-    this.editor.hooks.onPreviewRefresh = function() {
-      return self.afterRender();
-    };
-
-    this.editor.run();
-    this.set('editor', this.editor);
-    this.loadingChanged();
-
-    const saveDraft = debounce((function() {
-      return controller.saveDraft();
-    }), 2000);
-
-    $wmdInput.keyup(function() {
-      saveDraft();
-      return true;
-    });
-
-    const $replyTitle = $('#reply-title');
-
-    $replyTitle.keyup(function() {
-      saveDraft();
-      // removes the red background once the requirements are met
-      if (self.get('model.missingTitleCharacters') <= 0) {
-        $replyTitle.removeClass("requirements-not-met");
-      }
-      return true;
-    });
-
-    // when the title field loses the focus...
-    $replyTitle.blur(function(){
-      // ...and the requirements are not met (ie. the minimum number of characters)
-      if (self.get('model.missingTitleCharacters') > 0) {
-        // then, "redify" the background
-        $replyTitle.toggleClass("requirements-not-met", true);
-      }
-    });
-
-    // in case it's still bound somehow
-    this._unbindUploadTarget();
-
-    const $uploadTarget = $("#reply-control"),
-          csrf = Discourse.Session.currentProp("csrfToken"),
-          reset = () => this.setProperties({ uploadProgress: 0, isUploading: false });
-
-    var cancelledByTheUser;
-
-    this.messageBus.subscribe("/uploads/composer", upload => {
-      // reset upload state
-      reset();
-      // replace upload placeholder
-      if (upload && upload.url) {
-        if (!cancelledByTheUser) {
-          const uploadPlaceholder = Discourse.Utilities.getUploadPlaceholder(),
-                markdown = Discourse.Utilities.getUploadMarkdown(upload);
-          this.replaceMarkdown(uploadPlaceholder, markdown);
-        }
-      } else {
-        Discourse.Utilities.displayErrorForUpload(upload);
-      }
-    });
-
-    $uploadTarget.fileupload({
-      url: Discourse.getURL("/uploads.json?client_id=" + this.messageBus.clientId + "&authenticity_token=" + encodeURIComponent(csrf)),
-      dataType: "json",
-      pasteZone: $uploadTarget,
-    });
-
-    $uploadTarget.on("fileuploadsubmit", (e, data) => {
-      const isValid = Discourse.Utilities.validateUploadedFiles(data.files);
-      data.formData = { type: "composer" };
-      this.setProperties({ uploadProgress: 0, isUploading: isValid });
-      return isValid;
-    });
-
-    $uploadTarget.on("fileuploadsend", (e, data) => {
-      // hide the "file selector" modal
-      controller.send("closeModal");
-      // deal with cancellation
-      cancelledByTheUser = false;
-      // add upload placeholder
-      const uploadPlaceholder = Discourse.Utilities.getUploadPlaceholder();
-      this.addMarkdown(uploadPlaceholder);
-
-      if (data["xhr"]) {
-        const jqHXR = data.xhr();
-        if (jqHXR) {
-          // need to wait for the link to show up in the DOM
-          Em.run.schedule("afterRender", () => {
-            const $cancel = $("#cancel-file-upload");
-            $cancel.on("click", () => {
-              if (jqHXR) {
-                // signal the upload was cancelled by the user
-                cancelledByTheUser = true;
-                // immediately remove upload placeholder
-                this.replaceMarkdown(uploadPlaceholder, "");
-                // might trigger a "fileuploadfail" event with status = 0
-                jqHXR.abort();
-                // make sure we always reset the uploading status
-                reset();
-              }
-              // unbind
-              $cancel.off("click");
-            });
-          });
-        }
-      }
-    });
-
-    $uploadTarget.on("fileuploadprogressall", (e, data) => {
-      const progress = parseInt(data.loaded / data.total * 100, 10);
-      this.set("uploadProgress", progress);
-    });
-
-    $uploadTarget.on("fileuploadfail", (e, data) => {
-      // reset upload state
-      reset();
-
-      if (!cancelledByTheUser) {
-        // remove upload placeholder when there's a failure
-        const uploadPlaceholder = Discourse.Utilities.getUploadPlaceholder();
-        this.replaceMarkdown(uploadPlaceholder, "");
-        // display the error
-        Discourse.Utilities.displayErrorForUpload(data);
-      }
-    });
-
-    // contenteditable div hack for getting image paste to upload working in
-    // Firefox. This is pretty dangerous because it can potentially break
-    // Ctrl+v to paste so we should be conservative about what browsers this runs
-    // in.
-    const uaMatch = navigator.userAgent.match(/Firefox\/(\d+)\.\d/);
-    if (uaMatch && parseInt(uaMatch[1]) >= 24) {
-      self.$().append( Ember.$("<div id='contenteditable' contenteditable='true' style='height: 0; width: 0; overflow: hidden'></div>") );
-      self.$("textarea").off('keydown.contenteditable');
-      self.$("textarea").on('keydown.contenteditable', function(event) {
-        // Catch Ctrl+v / Cmd+v and hijack focus to a contenteditable div. We can't
-        // use the onpaste event because for some reason the paste isn't resumed
-        // after we switch focus, probably because it is being executed too late.
-        if ((event.ctrlKey || event.metaKey) && (event.keyCode === 86)) {
-          // Save the current textarea selection.
-          const textarea = self.$("textarea")[0],
-              selectionStart = textarea.selectionStart,
-              selectionEnd   = textarea.selectionEnd;
-
-          // Focus the contenteditable div.
-          const contentEditableDiv = self.$('#contenteditable');
-          contentEditableDiv.focus();
-
-          // The paste doesn't finish immediately and we don't have any onpaste
-          // event, so wait for 100ms which _should_ be enough time.
-          setTimeout(function() {
-            const pastedImg  = contentEditableDiv.find('img');
-
-            if ( pastedImg.length === 1 ) {
-              pastedImg.remove();
-            }
-
-            // For restoring the selection.
-            textarea.focus();
-            const textareaContent = $(textarea).val(),
-                startContent = textareaContent.substring(0, selectionStart),
-                endContent = textareaContent.substring(selectionEnd);
-
-            const restoreSelection = function(pastedText) {
-              $(textarea).val( startContent + pastedText + endContent );
-              textarea.selectionStart = selectionStart + pastedText.length;
-              textarea.selectionEnd = textarea.selectionStart;
-            };
-
-            if (contentEditableDiv.html().length > 0) {
-              // If the image wasn't the only pasted content we just give up and
-              // fall back to the original pasted text.
-              contentEditableDiv.find("br").replaceWith("\n");
-              restoreSelection(contentEditableDiv.text());
-            } else {
-              // Depending on how the image is pasted in, we may get either a
-              // normal URL or a data URI. If we get a data URI we can convert it
-              // to a Blob and upload that, but if it is a regular URL that
-              // operation is prevented for security purposes. When we get a regular
-              // URL let's just create an <img> tag for the image.
-              const imageSrc = pastedImg.attr('src');
-
-              if (imageSrc.match(/^data:image/)) {
-                // Restore the cursor position, and remove any selected text.
-                restoreSelection("");
-
-                // Create a Blob to upload.
-                const image = new Image();
-                image.onload = function() {
-                  // Create a new canvas.
-                  const canvas = document.createElementNS('http://www.w3.org/1999/xhtml', 'canvas');
-                  canvas.height = image.height;
-                  canvas.width = image.width;
-                  const ctx = canvas.getContext('2d');
-                  ctx.drawImage(image, 0, 0);
-
-                  canvas.toBlob(function(blob) {
-                    $uploadTarget.fileupload('add', {files: blob});
-                  });
-                };
-                image.src = imageSrc;
-              } else {
-                restoreSelection("<img src='" + imageSrc + "'>");
-              }
-            }
-
-            contentEditableDiv.html('');
-          }, 100);
-        }
-      });
-    }
-
-    if (Discourse.Mobile.mobileView) {
-      $(".mobile-file-upload").on("click.uploader", function () {
-        // redirect the click on the hidden file input
-        $("#mobile-uploader").click();
-      });
-    }
-
-    // need to wait a bit for the "slide up" transition of the composer
-    // we could use .on("transitionend") but it's not firing when the transition isn't completed :(
-    Em.run.later(function() {
-      self.resize();
-      self.refreshPreview();
-      if ($replyTitle.length) {
-        $replyTitle.putCursorAtEnd();
-      } else {
-        $wmdInput.putCursorAtEnd();
-      }
-      self.appEvents.trigger("composer:opened");
-    }, 400);
-  },
-
-  addMarkdown(text) {
-    const ctrl = this.$('.wmd-input').get(0),
-          reply = this.get('model.reply'),
-          caretPosition = Discourse.Utilities.caretPosition(ctrl);
-
-    this.set('model.reply', reply.substring(0, caretPosition) + text + reply.substring(caretPosition, reply.length));
-
-    Em.run.schedule('afterRender', () => Discourse.Utilities.setCaretPosition(ctrl, caretPosition + text.length));
-  },
-
-  replaceMarkdown(old, text) {
-    const ctrl = this.$(".wmd-input").get(0),
-          reply = this.get("model.reply"),
-          beforeCaretPosition = Discourse.Utilities.caretPosition(ctrl),
-          afterCaretPosition = beforeCaretPosition <= reply.indexOf(old) ? beforeCaretPosition :  beforeCaretPosition - old.length + text.length;
-
-    this.set("model.reply", reply.replace(old, text));
-
-    Ember.run.schedule("afterRender", () => Discourse.Utilities.setCaretPosition(ctrl, afterCaretPosition));
-  },
-
-  // Uses javascript to get the image sizes from the preview, if present
-  imageSizes() {
-    const result = {};
-    this.$('.wmd-preview img').each(function(i, e) {
-      const $img = $(e),
-          src = $img.prop('src');
-
-      if (src && src.length) {
-        result[src] = { width: $img.width(), height: $img.height() };
-      }
-    });
-    return result;
-  },
-
-  childDidInsertElement() {
-    this.initEditor();
-
-    // Disable links in the preview
-    this.$('.wmd-preview').on('click.preview', (e) => {
-      e.preventDefault();
-      return false;
-    });
-  },
-
-  childWillDestroyElement() {
-    this._unbindUploadTarget();
-
-    this.$('.wmd-preview').off('click.preview');
-
-    const self = this;
-
-    Em.run.next(() => {
-      $('#main-outlet').css('padding-bottom', 0);
-      // need to wait a bit for the "slide down" transition of the composer
-      Em.run.later(() => {
-        if (self.get('composeState') !== Discourse.Composer.CLOSED) {
-          $('#main-outlet').css('padding-bottom', $('#reply-control').height());
-        }
-
-        this.appEvents.trigger("composer:closed");
-      }, 400);
-    });
-  },
-
-  _unbindUploadTarget() {
-    this.messageBus.unsubscribe("/uploads/composer");
-    const $uploadTarget = $("#reply-control");
-    try { $uploadTarget.fileupload("destroy"); }
-    catch (e) { /* wasn't initialized yet */ }
-    $uploadTarget.off();
-  },
-
-  titleValidation: function() {
-    const titleLength = this.get('model.titleLength'),
-        missingChars = this.get('model.missingTitleCharacters');
-    let reason;
-    if( titleLength < 1 ){
-      reason = I18n.t('composer.error.title_missing');
-    } else if( missingChars > 0 ) {
-      reason = I18n.t('composer.error.title_too_short', {min: this.get('model.minimumTitleLength')});
-    } else if( titleLength > Discourse.SiteSettings.max_topic_title_length ) {
-      reason = I18n.t('composer.error.title_too_long', {max: Discourse.SiteSettings.max_topic_title_length});
-    }
-
-    if( reason ) {
-      return Discourse.InputValidation.create({ failed: true, reason: reason });
-    }
-  }.property('model.titleLength', 'model.missingTitleCharacters', 'model.minimumTitleLength'),
-
-  categoryValidation: function() {
-    if( !Discourse.SiteSettings.allow_uncategorized_topics && !this.get('model.categoryId')) {
-      return Discourse.InputValidation.create({ failed: true, reason: I18n.t('composer.error.category_missing') });
-    }
-  }.property('model.categoryId'),
-
-  replyValidation: function() {
-    const postType = this.get('model.post.post_type');
-    if (postType === this.site.get('post_types.small_action')) { return; }
-
-    const replyLength = this.get('model.replyLength'),
-          missingChars = this.get('model.missingReplyCharacters');
-
-    let reason;
-    if (replyLength < 1) {
-      reason = I18n.t('composer.error.post_missing');
-    } else if (missingChars > 0) {
-      reason = I18n.t('composer.error.post_length', {min: this.get('model.minimumPostLength')});
-      const tl = Discourse.User.currentProp("trust_level");
-      if (tl === 0 || tl === 1) {
-        reason += "<br/>" + I18n.t('composer.error.try_like');
-      }
-    }
-
-    if (reason) {
-      return Discourse.InputValidation.create({ failed: true, reason });
-    }
-  }.property('model.reply', 'model.replyLength', 'model.missingReplyCharacters', 'model.minimumPostLength'),
+  }
 });
 
 RSVP.EventTarget.mixin(ComposerView);
-
 export default ComposerView;
diff --git a/app/assets/javascripts/discourse/views/quote-button.js.es6 b/app/assets/javascripts/discourse/views/quote-button.js.es6
index 8f4c5ab66dc..da9ba9040c8 100644
--- a/app/assets/javascripts/discourse/views/quote-button.js.es6
+++ b/app/assets/javascripts/discourse/views/quote-button.js.es6
@@ -36,9 +36,8 @@ export default Ember.View.extend({
     // the quote reply widget
     //
     // Same hack applied to Android cause it has unreliable touchend
-    const caps = this.capabilities;
-    const android = caps.get('android');
-    if (caps.get('winphone') || android) {
+    const isAndroid = this.capabilities.isAndroid;
+    if (this.capabilities.isWinphone || isAndroid) {
       onSelectionChanged = _.debounce(onSelectionChanged, 500);
     }
 
@@ -72,7 +71,7 @@ export default Ember.View.extend({
 
       // Android is dodgy, touchend often will not fire
       // https://code.google.com/p/android/issues/detail?id=19827
-      if (!android) {
+      if (!isAndroid) {
         $(document)
           .on('touchstart.quote-button', function(){
             view.set('isTouchInProgress', true);
diff --git a/app/assets/javascripts/discourse/views/topic-map-container.js.es6 b/app/assets/javascripts/discourse/views/topic-map-container.js.es6
index e13a1ae4101..5bd42eb3675 100644
--- a/app/assets/javascripts/discourse/views/topic-map-container.js.es6
+++ b/app/assets/javascripts/discourse/views/topic-map-container.js.es6
@@ -1,5 +1,5 @@
 import ContainerView from 'discourse/views/container';
-import { default as property, observes, on } from 'ember-addons/ember-computed-decorators';
+import { default as computed, observes, on } from 'ember-addons/ember-computed-decorators';
 
 export default ContainerView.extend({
   classNameBindings: ['hidden', ':topic-map'],
@@ -9,7 +9,7 @@ export default ContainerView.extend({
     Ember.run.once(this, 'rerender');
   },
 
-  @property
+  @computed
   hidden() {
     if (!this.get('post.firstPost')) return true;
 
diff --git a/app/assets/javascripts/discourse/views/topic-progress.js.es6 b/app/assets/javascripts/discourse/views/topic-progress.js.es6
index b539b618b4f..6bb2604ac04 100644
--- a/app/assets/javascripts/discourse/views/topic-progress.js.es6
+++ b/app/assets/javascripts/discourse/views/topic-progress.js.es6
@@ -76,7 +76,7 @@ export default Ember.View.extend({
   _focusWhenOpened: function() {
 
     // Don't focus on mobile or touch
-    if (Discourse.Mobile.mobileView || this.capabilities.get('touch')) {
+    if (Discourse.Mobile.mobileView || this.capabilities.touch) {
       return;
     }
 
diff --git a/app/assets/javascripts/discourse/views/upload-selector.js.es6 b/app/assets/javascripts/discourse/views/upload-selector.js.es6
index 4bf80f2aad8..7f6af6752bc 100644
--- a/app/assets/javascripts/discourse/views/upload-selector.js.es6
+++ b/app/assets/javascripts/discourse/views/upload-selector.js.es6
@@ -1,74 +1,33 @@
 import ModalBodyView from "discourse/views/modal-body";
+import { default as computed, on, observes } from 'ember-addons/ember-computed-decorators';
+import { uploadTranslate } from 'discourse/controllers/upload-selector';
 
-function uploadTranslate(key, options) {
-  const opts = options || {};
-  if (Discourse.Utilities.allowsAttachments()) { key += "_with_attachments"; }
-  return I18n.t("upload_selector." + key, opts);
-}
 
 export default ModalBodyView.extend({
-  templateName: 'modal/upload_selector',
+  templateName: 'modal/upload-selector',
   classNames: ['upload-selector'],
 
-  // cf. http://stackoverflow.com/a/9851769/11983
-  isOpera: !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0,
-  isFirefox: typeof InstallTrigger !== 'undefined',
-  isSafari: Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0,
-  isChrome: !!window.chrome && !this.isOpera,
+  @computed()
+  title() {
+    return uploadTranslate("title");
+  },
 
-  title: function() { return uploadTranslate("title"); }.property(),
-  uploadIcon: function() { return Discourse.Utilities.allowsAttachments() ? "fa-upload" : "fa-picture-o"; }.property(),
-
-  touchStart: function(evt) {
+  touchStart(evt) {
     // HACK: workaround Safari iOS being really weird and not shipping click events
-    if (this.isSafari && evt.target.id === "filename-input") {
+    if (this.capabilities.isSafari && evt.target.id === "filename-input") {
       this.$('#filename-input').click();
     }
   },
 
-  tip: function() {
-    const source = this.get("controller.local") ? "local" : "remote";
-    const authorized_extensions = Discourse.Utilities.authorizesAllExtensions() ? "" : `(${Discourse.Utilities.authorizedExtensions()})`;
-    return uploadTranslate(source + "_tip", { authorized_extensions });
-  }.property("controller.local"),
-
-  hint: function() {
-    const isSupported = this.isChrome || this.isFirefox;
-    // chrome is the only browser that support copy & paste of images.
-    return I18n.t("upload_selector.hint" + (isSupported ? "_for_supported_browsers" : ""));
-  }.property(),
-
-  _selectOnInsert: function() {
-    this.selectedChanged();
-  }.on('didInsertElement'),
-
-  selectedChanged: function() {
-    const self = this;
-    Em.run.next(function() {
+  @on('didInsertElement')
+  @observes('controller.local')
+  selectedChanged() {
+    Ember.run.next(() => {
       // *HACK* to select the proper radio button
-      var value = self.get('controller.local') ? 'local' : 'remote';
+      const value = this.get('controller.local') ? 'local' : 'remote';
       $('input:radio[name="upload"]').val([value]);
-      // focus the input
       $('.inputs input:first').focus();
     });
-  }.observes('controller.local'),
-
-  actions: {
-    upload: function() {
-      if (this.get("controller.local")) {
-        $('#reply-control').fileupload('add', { fileInput: $('#filename-input') });
-      } else {
-        const imageUrl = $('#fileurl-input').val(),
-              imageLink = $('#link-input').val(),
-              composerView = this.get('controller.composerView');
-        if (this.get("controller.showMore") && imageLink.length > 3) {
-          composerView.addMarkdown("[![](" + imageUrl +")](" + imageLink + ")");
-        } else {
-          composerView.addMarkdown(imageUrl);
-        }
-        this.get('controller').send('closeModal');
-      }
-    }
   }
 
 });
diff --git a/app/assets/javascripts/main_include.js b/app/assets/javascripts/main_include.js
index fbb72ad3f31..853d0d5e241 100644
--- a/app/assets/javascripts/main_include.js
+++ b/app/assets/javascripts/main_include.js
@@ -1,9 +1,6 @@
 //= require ./discourse/mixins/ajax
 //= require ./discourse
 
-// Pagedown customizations
-//= require ./pagedown_custom.js
-
 // Stuff we need to load first
 //= require_tree ./ember-addons/utils
 //= require ./ember-addons/decorator-alias
@@ -77,6 +74,7 @@
 //= require ./discourse/lib/emoji/emoji
 //= require ./discourse/lib/emoji/emoji-groups
 //= require ./discourse/lib/emoji/emoji-toolbar
+//= require ./discourse/components/d-editor
 //= require ./discourse/views/composer
 //= require ./discourse/lib/show-modal
 //= require ./discourse/lib/screen-track
diff --git a/app/assets/javascripts/pagedown_custom.js b/app/assets/javascripts/pagedown_custom.js
deleted file mode 100644
index 8dec5168116..00000000000
--- a/app/assets/javascripts/pagedown_custom.js
+++ /dev/null
@@ -1,37 +0,0 @@
-window.PagedownCustom = {
-  insertButtons: [
-    {
-      id: 'wmd-quote-post',
-      description: I18n.t("composer.quote_post_title"),
-      execute: function() {
-        return Discourse.__container__.lookup('controller:composer').send('importQuote');
-      }
-    }
-  ],
-
-  appendButtons: [],
-
-  customActions: {
-    "doBlockquote": function(chunk, postProcessing, oldDoBlockquote) {
-
-      // When traditional linebreaks are set, use the default Pagedown implementation
-      if (Discourse.SiteSettings.traditional_markdown_linebreaks) {
-        return oldDoBlockquote.call(this, chunk, postProcessing);
-      }
-
-      // Our custom blockquote for non-traditional markdown linebreaks
-      var result = [];
-      chunk.selection.split(/\n/).forEach(function (line) {
-        var newLine = "";
-        if (line.indexOf("> ") === 0) {
-          newLine += line.substr(2);
-        } else {
-          if (/\S/.test(line)) { newLine += "> " + line; }
-        }
-        result.push(newLine);
-      });
-      chunk.selection = result.join("\n");
-
-    }
-  }
-};
diff --git a/app/assets/stylesheets/common/admin/admin_base.scss b/app/assets/stylesheets/common/admin/admin_base.scss
index d4ab16ec4f7..55f37c06b73 100644
--- a/app/assets/stylesheets/common/admin/admin_base.scss
+++ b/app/assets/stylesheets/common/admin/admin_base.scss
@@ -1188,7 +1188,7 @@ table.api-keys {
     height: 200px;
   }
 
-  .wmd-input {
+  .d-editor-input {
     width: 98%;
     height: 200px;
   }
diff --git a/app/assets/stylesheets/common/base/compose.scss b/app/assets/stylesheets/common/base/compose.scss
index 56bfa280761..a2766118669 100644
--- a/app/assets/stylesheets/common/base/compose.scss
+++ b/app/assets/stylesheets/common/base/compose.scss
@@ -38,7 +38,7 @@
   }
 }
 
-.textarea-wrapper .spinner {
+.d-editor-textarea-wrapper .spinner {
   z-index: 1000;
   margin-top: 5em;
 }
@@ -99,10 +99,6 @@ div.ac-wrap {
   }
 }
 
-#reply-control.topic #wmd-quote-post {
-  display: none;
-}
-
 .auto-close-fields {
   div:not(:first-child) {
     margin-top: 10px;
@@ -175,7 +171,7 @@ div.ac-wrap {
 
 // this removes the topmost margin from the first element in the topic post
 // if we don't do this, all posts would have extra space at the top
-.wmd-preview > *:first-child {
+.d-editor-preview > *:first-child {
   margin-top: 0;
 }
 .cooked > *:first-child {
diff --git a/app/assets/stylesheets/common/base/discourse.scss b/app/assets/stylesheets/common/base/discourse.scss
index 2580ff1effe..95ccddffbc6 100644
--- a/app/assets/stylesheets/common/base/discourse.scss
+++ b/app/assets/stylesheets/common/base/discourse.scss
@@ -149,7 +149,7 @@ body {
     background-color: dark-light-choose(scale-color($danger, $lightness: 80%), scale-color($danger, $lightness: -60%));
   }
 
-  .wmd-input {
+  .d-editor-input {
     resize: none;
   }
 
diff --git a/app/assets/stylesheets/common/base/pagedown.scss b/app/assets/stylesheets/common/base/pagedown.scss
deleted file mode 100644
index 1ee211aa503..00000000000
--- a/app/assets/stylesheets/common/base/pagedown.scss
+++ /dev/null
@@ -1,145 +0,0 @@
-// styles that apply to the PageDown editor
-// http://code.google.com/p/pagedown/
-
-.wmd-panel {
-  margin-left: 25%;
-  margin-right: 25%;
-  width: 50%;
-  min-width: 500px;
-}
-
-.wmd-button-bar {
-  width: 100%;
-}
-
-.wmd-button-row {
-  margin: 5px;
-  padding: 0;
-  height: 20px;
-  overflow: hidden;
-}
-
-.wmd-spacer {
-  width: 1px;
-  height: 20px;
-  margin-right: 8px;
-  margin-left: 5px;
-  background-color: dark-light-diff($primary, $secondary, 90%, -60%);
-  display: inline-block;
-  float: left;
-}
-
-.wmd-button {
-  margin-right: 5px;
-  border: 0;
-  position: relative;
-  float: left;
-  font-family: FontAwesome;
-  font-weight: normal;
-  font-style: normal;
-  text-decoration: inherit;
-  display: inline;
-  width: auto;
-  height: auto;
-  line-height: normal;
-  vertical-align: baseline;
-  background-image: none !important;
-  background-position: 0 0;
-  background-repeat: repeat;
-  background: transparent;
-  padding: 4px;
-}
-
-.wmd-button:hover {
-  background-color: dark-light-diff($primary, $secondary, 90%, -60%);
-}
-
-
-.wmd-bold-button:before {
-  content: "\f032";
-}
-
-.wmd-italic-button:before {
-  content: "\f033";
-}
-
-.wmd-link-button:before {
-  content: "\f0c1";
-}
-
-.wmd-quote-button:before {
-  content: "\f10e";
-}
-
-.wmd-code-button:before {
-  content: "\f121";
-}
-
-.wmd-image-button:before {
-  content: "\f093";
-}
-
-.wmd-image-button.image-only:before {
-  content: "\f03e";
-}
-
-.wmd-olist-button:before {
-  content: "\f0cb";
-}
-
-.wmd-ulist-button:before {
-  content: "\f0ca";
-}
-
-.wmd-heading-button:before {
-  content:  "\f031";
-}
-
-.wmd-hr-button:before {
-  content:  "\f068";
-}
-
-.wmd-undo-button:before {
-  content:  "\f0e2";
-}
-
-.wmd-redo-button:before {
-  content:  "\f01e";
-}
-
-.wmd-quote-post:before {
-  content:  "\f0e5";
-}
-
-.wmd-composer-options:before {
-  content:  "\f013";
-}
-
-.wmd-prompt-background {
-  background-color: #111;
-  box-shadow: 0 3px 7px rgba(0,0,0, .8);
-}
-
-.wmd-prompt-dialog {
-  border: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
-  background-color: dark-light-diff($primary, $secondary, 90%, -60%);
-}
-
-.wmd-prompt-dialog > div {
-  font-size: 0.8em;
-  font-family: arial, helvetica, sans-serif;
-}
-
-.wmd-prompt-dialog > form > input[type="text"] {
-  border: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
-  color: $primary;
-}
-
-.wmd-prompt-dialog > form > input[type="button"] {
-  border: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
-  background: dark-light-choose(initial, blend-primary-secondary(50%));
-  color: dark-light-choose(inherit, $secondary);
-  font-family: trebuchet MS, helvetica, sans-serif;
-  font-size: 0.8em;
-  font-weight: bold;
-}
diff --git a/app/assets/stylesheets/common/base/topic-post.scss b/app/assets/stylesheets/common/base/topic-post.scss
index dab4f08f13f..02cacad3280 100644
--- a/app/assets/stylesheets/common/base/topic-post.scss
+++ b/app/assets/stylesheets/common/base/topic-post.scss
@@ -26,7 +26,7 @@
 }
 
 // global styles for the cooked HTML content in posts (and preview)
-.cooked, .wmd-preview {
+.cooked, .d-editor-preview {
   word-wrap: break-word;
   h1, h2, h3, h4, h5, h6 { margin: 30px 0 10px; }
   h1 { line-height: 1em; } /* normalize.css sets h1 font size but not line height */
@@ -36,7 +36,7 @@
 }
 
 
-.cooked, .wmd-preview {
+.cooked, .d-editor-preview {
   video {
     max-width: 100%;
   }
diff --git a/app/assets/stylesheets/desktop/compose.scss b/app/assets/stylesheets/desktop/compose.scss
index 18faf89732f..c3a5f73094e 100644
--- a/app/assets/stylesheets/desktop/compose.scss
+++ b/app/assets/stylesheets/desktop/compose.scss
@@ -278,14 +278,14 @@
         background-color: dark-light-diff($primary, $secondary, 90%, -60%);
       }
     }
-    .wmd-input:disabled {
+    .d-editor-input:disabled {
       background-color: dark-light-diff($primary, $secondary, 90%, -60%);
     }
-    .wmd-input, .wmd-preview {
+    .d-editor-input, .d-editor-preview {
       color: $primary;
     }
 
-    .wmd-preview {
+    .d-editor-preview {
       border: 1px dashed dark-light-diff($primary, $secondary, 90%, -60%);
       overflow: auto;
       visibility: visible;
@@ -303,7 +303,7 @@
         visibility: hidden;
       }
     }
-    .wmd-input {
+    .d-editor-input {
       bottom: 35px;
     }
 
@@ -351,19 +351,18 @@
 }
 
 #reply-control {
-  &.hide-preview {
-    .wmd-controls {
-      .wmd-input {
-        width: 100%;
-      }
-      .preview-wrapper {
-        display: none;
-      }
-      .textarea-wrapper {
-        width: 100%;
-      }
+  .wmd-controls.hide-preview {
+    .d-editor-input {
+      width: 100%;
+    }
+    .d-editor-preview-wrapper {
+      display: none;
+    }
+    .d-editor-textarea-wrapper {
+      width: 100%;
     }
   }
+
   .wmd-controls {
     left: 30px;
     right: 30px;
@@ -372,7 +371,7 @@
     top: 50px;
 
 
-    .wmd-input, .wmd-preview-scroller, .wmd-preview {
+    .d-editor-input, .d-editor-preview {
       -moz-box-sizing: border-box;
       box-sizing: border-box;
       width: 100%;
@@ -383,7 +382,7 @@
       background-color: $secondary;
       word-wrap: break-word;
     }
-    .wmd-input, .wmd-preview-scroller {
+    .d-editor-input, .d-editor-preview-header {
       position: absolute;
       left: 0;
       top: 0;
@@ -391,18 +390,17 @@
       border-top: 30px solid transparent;
       @include border-radius-all(0);
     }
-    .wmd-preview-scroller {
+    .d-editor-preview-header {
       font-size: 0.929em;
       line-height: 18px;
       font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
       overflow: scroll;
-      visibility: hidden;
       .marker, .caret {
         display: inline-block;
         vertical-align: top;
       }
     }
-    .textarea-wrapper, .preview-wrapper {
+    .d-editor, .d-editor-container, .d-editor-textarea-wrapper, .d-editor-preview-wrapper {
       position: relative;
       -moz-box-sizing: border-box;
       box-sizing: border-box;
@@ -410,9 +408,9 @@
       min-height: 100%;
       margin: 0;
       padding: 0;
-      width: 50%;
     }
-    .textarea-wrapper {
+    .d-editor-textarea-wrapper {
+      width: 50%;
       padding-right: 5px;
       float: left;
       .popup-tip {
@@ -420,12 +418,13 @@
         right: 4px;
       }
     }
-    .preview-wrapper {
+    .d-editor-preview-wrapper {
+      width: 50%;
       padding-left: 5px;
       float: right;
     }
   }
-  .wmd-button-bar {
+  .d-editor-button-bar {
     top: 0;
     position: absolute;
     border-bottom: 1px solid dark-light-diff($primary, $secondary, 90%, -60%);
diff --git a/app/assets/stylesheets/desktop/queued-posts.scss b/app/assets/stylesheets/desktop/queued-posts.scss
index 06e24ab1e15..6d306bae6ee 100644
--- a/app/assets/stylesheets/desktop/queued-posts.scss
+++ b/app/assets/stylesheets/desktop/queued-posts.scss
@@ -18,7 +18,7 @@
       width: $topic-body-width;
       float: left;
 
-      .wmd-input {
+      .d-editor-input {
         width: 98%;
         height: 15em;
       }
diff --git a/app/assets/stylesheets/desktop/user.scss b/app/assets/stylesheets/desktop/user.scss
index cd1f837e67a..10a6b9d4558 100644
--- a/app/assets/stylesheets/desktop/user.scss
+++ b/app/assets/stylesheets/desktop/user.scss
@@ -39,10 +39,6 @@
     }
   }
 
-  .bio-composer #wmd-quote-post {
-    display: none;
-  }
-
   .static {
     color: $primary;
     display: inline-block;
diff --git a/app/assets/stylesheets/mobile/compose.scss b/app/assets/stylesheets/mobile/compose.scss
index d63afa772de..b477ca6f2c8 100644
--- a/app/assets/stylesheets/mobile/compose.scss
+++ b/app/assets/stylesheets/mobile/compose.scss
@@ -163,13 +163,13 @@ input {
         background-color: dark-light-choose(scale-color($primary, $lightness: 75%), scale-color($secondary, $lightness: 25%));
       }
     }
-    .wmd-input:disabled {
+    .d-editor-input:disabled {
       background-color: dark-light-choose(scale-color($primary, $lightness: 75%), scale-color($secondary, $lightness: 25%));
     }
-    .wmd-input {
+    .d-editor-input {
       color: dark-light-choose(darken($primary, 40%), blend-primary-secondary(90%));
     }
-    .wmd-input {
+    .d-editor-input {
       bottom: 35px;
     }
     .submit-panel {
@@ -196,7 +196,7 @@ input {
     width: 240px;
     right: 5px;
   }
-  .textarea-wrapper .popup-tip {
+  .d-editor-textarea-wrapper .popup-tip {
     top: 28px;
   }
   button.btn.no-text {
@@ -221,23 +221,22 @@ input {
     top: 40px;
     bottom: 50px;
     display: block;
-
-    .wmd-input {
+    .d-editor-container {
+      padding: 0;
+    }
+    .d-editor-preview-wrapper {
+      display: none;
+    }
+    .d-editor-input {
       width: 100%;
-      height: 100%;
-      min-height: 100%;
+      height: 180px;
       padding: 7px;
       margin: 0;
       background-color: $secondary;
       word-wrap: break-word;
       box-sizing: border-box;
     }
-    .wmd-input {
-      position: absolute;
-      left: 0;
-      top: 0;
-    }
-    .textarea-wrapper {
+    .d-editor-textarea-wrapper {
       position: relative;
       box-sizing: border-box;
       height: 100%;
@@ -250,7 +249,7 @@ input {
       }
     }
   }
-  .wmd-button-bar {
+  .d-editor-button-bar {
     display: none;
   }
 }
diff --git a/app/assets/stylesheets/mobile/user.scss b/app/assets/stylesheets/mobile/user.scss
index 58e9ed8f0b9..7398fc6b5f5 100644
--- a/app/assets/stylesheets/mobile/user.scss
+++ b/app/assets/stylesheets/mobile/user.scss
@@ -63,10 +63,6 @@
     padding: 5px 8px;
   }
 
-  .bio-composer #wmd-quote-post {
-    display: none;
-  }
-
   textarea {width: 100%;}
 }
 
@@ -99,10 +95,6 @@
     }
   }
 
-  .bio-composer #wmd-quote-post {
-    display: none;
-  }
-
   .static {
     color: $primary;
     display: inline-block;
diff --git a/spec/phantom_js/smoke_test.js b/spec/phantom_js/smoke_test.js
index 94e69310204..2399ea848dc 100644
--- a/spec/phantom_js/smoke_test.js
+++ b/spec/phantom_js/smoke_test.js
@@ -179,12 +179,12 @@ var runTests = function() {
 
     $("#create-topic").click();
     $("#reply-title").val(title).trigger("change");
-    $("#reply-control .wmd-input").val(post).trigger("change");
-    $("#reply-control .wmd-input").focus()[0].setSelectionRange(post.length, post.length);
+    $("#reply-control .d-editor-input").val(post).trigger("change");
+    $("#reply-control .d-editor-input").focus()[0].setSelectionRange(post.length, post.length);
   });
 
   exec("open upload modal", function() {
-    $(".wmd-image-button").click();
+    $(".d-editor-button-bar .upload").click();
   });
 
   test("upload modal is open", function() {
@@ -214,16 +214,16 @@ var runTests = function() {
   });
 
   test("composer is open", function() {
-    return document.querySelector("#reply-control .wmd-input");
+    return document.querySelector("#reply-control .d-editor-input");
   });
 
   exec("compose reply", function() {
     var post = "I can even write a reply inside the smoke test ;) (" + (+new Date()) + ")";
-    $("#reply-control .wmd-input").val(post).trigger("change");
+    $("#reply-control .d-editor-input").val(post).trigger("change");
   });
 
   test("waiting for the preview", function() {
-    return $(".wmd-preview").text().trim().indexOf("I can even write") === 0;
+    return $(".d-editor-preview").text().trim().indexOf("I can even write") === 0;
   });
 
   execAsync("submit the reply", 6000, function() {
diff --git a/test/javascripts/acceptance/composer-test.js.es6 b/test/javascripts/acceptance/composer-test.js.es6
index 835a3429642..76966aa689e 100644
--- a/test/javascripts/acceptance/composer-test.js.es6
+++ b/test/javascripts/acceptance/composer-test.js.es6
@@ -10,25 +10,25 @@ test("Tests the Composer controls", () => {
 
   click('#create-topic');
   andThen(() => {
-    ok(exists('.wmd-input'), 'the composer input is visible');
+    ok(exists('.d-editor-input'), 'the composer input is visible');
     ok(exists('.title-input .popup-tip.bad.hide'), 'title errors are hidden by default');
-    ok(exists('.textarea-wrapper .popup-tip.bad.hide'), 'body errors are hidden by default');
+    ok(exists('.d-editor-textarea-wrapper .popup-tip.bad.hide'), 'body errors are hidden by default');
   });
 
   click('a.toggle-preview');
   andThen(() => {
-    ok(!exists('.wmd-preview:visible'), "clicking the toggle hides the preview");
+    ok(!exists('.d-editor-preview:visible'), "clicking the toggle hides the preview");
   });
 
   click('a.toggle-preview');
   andThen(() => {
-    ok(exists('.wmd-preview:visible'), "clicking the toggle shows the preview again");
+    ok(exists('.d-editor-preview:visible'), "clicking the toggle shows the preview again");
   });
 
   click('#reply-control button.create');
   andThen(() => {
     ok(!exists('.title-input .popup-tip.bad.hide'), 'it shows the empty title error');
-    ok(!exists('.textarea-wrapper .popup-tip.bad.hide'), 'it shows the empty body error');
+    ok(!exists('.d-editor-wrapper .popup-tip.bad.hide'), 'it shows the empty body error');
   });
 
   fillIn('#reply-title', "this is my new topic title");
@@ -36,10 +36,10 @@ test("Tests the Composer controls", () => {
     ok(exists('.title-input .popup-tip.good'), 'the title is now good');
   });
 
-  fillIn('.wmd-input', "this is the *content* of a post");
+  fillIn('.d-editor-input', "this is the *content* of a post");
   andThen(() => {
-    equal(find('.wmd-preview').html(), "<p>this is the <em>content</em> of a post</p>", "it previews content");
-    ok(exists('.textarea-wrapper .popup-tip.good'), 'the body is now good');
+    equal(find('.d-editor-preview').html().trim(), "<p>this is the <em>content</em> of a post</p>", "it previews content");
+    ok(exists('.d-editor-textarea-wrapper .popup-tip.good'), 'the body is now good');
   });
 
   click('#reply-control a.cancel');
@@ -58,7 +58,7 @@ test("Create a topic with server side errors", () => {
   visit("/");
   click('#create-topic');
   fillIn('#reply-title', "this title triggers an error");
-  fillIn('.wmd-input', "this is the *content* of a post");
+  fillIn('.d-editor-input', "this is the *content* of a post");
   click('#reply-control button.create');
   andThen(() => {
     ok(exists('.bootbox.modal'), 'it pops up an error message');
@@ -66,7 +66,7 @@ test("Create a topic with server side errors", () => {
   click('.bootbox.modal a.btn-primary');
   andThen(() => {
     ok(!exists('.bootbox.modal'), 'it dismisses the error');
-    ok(exists('.wmd-input'), 'the composer input is visible');
+    ok(exists('.d-editor-input'), 'the composer input is visible');
   });
 });
 
@@ -74,7 +74,7 @@ test("Create a Topic", () => {
   visit("/");
   click('#create-topic');
   fillIn('#reply-title', "Internationalization Localization");
-  fillIn('.wmd-input', "this is the *content* of a new topic post");
+  fillIn('.d-editor-input', "this is the *content* of a new topic post");
   click('#reply-control button.create');
   andThen(() => {
     equal(currentURL(), "/t/internationalization-localization/280", "it transitions to the newly created topic URL");
@@ -85,7 +85,7 @@ test("Create an enqueued Topic", () => {
   visit("/");
   click('#create-topic');
   fillIn('#reply-title', "Internationalization Localization");
-  fillIn('.wmd-input', "enqueue this content please");
+  fillIn('.d-editor-input', "enqueue this content please");
   click('#reply-control button.create');
   andThen(() => {
     ok(visible('#discourse-modal'), 'it pops up a modal');
@@ -108,11 +108,11 @@ test("Create a Reply", () => {
 
   click('#topic-footer-buttons .btn.create');
   andThen(() => {
-    ok(exists('.wmd-input'), 'the composer input is visible');
+    ok(exists('.d-editor-input'), 'the composer input is visible');
     ok(!exists('#reply-title'), 'there is no title since this is a reply');
   });
 
-  fillIn('.wmd-input', 'this is the content of my reply');
+  fillIn('.d-editor-input', 'this is the content of my reply');
   click('#reply-control button.create');
   andThen(() => {
     equal(find('.cooked:last p').text(), 'this is the content of my reply');
@@ -122,7 +122,7 @@ test("Create a Reply", () => {
 test("Posting on a different topic", (assert) => {
   visit("/t/internationalization-localization/280");
   click('#topic-footer-buttons .btn.create');
-  fillIn('.wmd-input', 'this is the content for a different topic');
+  fillIn('.d-editor-input', 'this is the content for a different topic');
 
   visit("/t/1-3-0beta9-no-rate-limit-popups/28830");
   andThen(function() {
@@ -145,11 +145,11 @@ test("Create an enqueued Reply", () => {
 
   click('#topic-footer-buttons .btn.create');
   andThen(() => {
-    ok(exists('.wmd-input'), 'the composer input is visible');
+    ok(exists('.d-editor-input'), 'the composer input is visible');
     ok(!exists('#reply-title'), 'there is no title since this is a reply');
   });
 
-  fillIn('.wmd-input', 'enqueue this content please');
+  fillIn('.d-editor-input', 'enqueue this content please');
   click('#reply-control button.create');
   andThen(() => {
     ok(find('.cooked:last p').text() !== 'enqueue this content please', "it doesn't insert the post");
@@ -173,14 +173,14 @@ test("Edit the first post", () => {
   click('.topic-post:eq(0) button[data-action=showMoreActions]');
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('Any plans to support'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('Any plans to support'), 0, 'it populates the input with the post text');
   });
 
-  fillIn('.wmd-input', "This is the new text for the post");
+  fillIn('.d-editor-input', "This is the new text for the post");
   fillIn('#reply-title', "This is the new text for the title");
   click('#reply-control button.create');
   andThen(() => {
-    ok(!exists('.wmd-input'), 'it closes the composer');
+    ok(!exists('.d-editor-input'), 'it closes the composer');
     ok(exists('.topic-post:eq(0) .post-info.edits'), 'it has the edits icon');
     ok(find('#topic-title h1').text().indexOf('This is the new text for the title') !== -1, 'it shows the new title');
     ok(find('.topic-post:eq(0) .cooked').text().indexOf('This is the new text for the post') !== -1, 'it updates the post');
@@ -192,11 +192,11 @@ test("Composer can switch between edits", () => {
 
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
   });
   click('.topic-post:eq(1) button[data-action=edit]');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the second post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the second post.'), 0, 'it populates the input with the post text');
   });
 });
 
@@ -204,14 +204,14 @@ test("Composer with dirty edit can toggle to another edit", () => {
   visit("/t/this-is-a-test-topic/9");
 
   click('.topic-post:eq(0) button[data-action=edit]');
-  fillIn('.wmd-input', 'This is a dirty reply');
+  fillIn('.d-editor-input', 'This is a dirty reply');
   click('.topic-post:eq(1) button[data-action=edit]');
   andThen(() => {
     ok(exists('.bootbox.modal'), 'it pops up a confirmation dialog');
   });
   click('.modal-footer a:eq(0)');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the second post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the second post.'), 0, 'it populates the input with the post text');
   });
 });
 
@@ -220,15 +220,15 @@ test("Composer can toggle between edit and reply", () => {
 
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
   });
   click('.topic-post:eq(0) button[data-action=reply]');
   andThen(() => {
-    equal(find('.wmd-input').val(), "", 'it clears the input');
+    equal(find('.d-editor-input').val(), "", 'it clears the input');
   });
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
   });
 });
 
@@ -236,14 +236,14 @@ test("Composer with dirty reply can toggle to edit", () => {
   visit("/t/this-is-a-test-topic/9");
 
   click('.topic-post:eq(0) button[data-action=reply]');
-  fillIn('.wmd-input', 'This is a dirty reply');
+  fillIn('.d-editor-input', 'This is a dirty reply');
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
     ok(exists('.bootbox.modal'), 'it pops up a confirmation dialog');
   });
   click('.modal-footer a:eq(0)');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
   });
 });
 
@@ -251,7 +251,7 @@ test("Composer draft with dirty reply can toggle to edit", () => {
   visit("/t/this-is-a-test-topic/9");
 
   click('.topic-post:eq(0) button[data-action=reply]');
-  fillIn('.wmd-input', 'This is a dirty reply');
+  fillIn('.d-editor-input', 'This is a dirty reply');
   click('.toggler');
   click('.topic-post:eq(0) button[data-action=edit]');
   andThen(() => {
@@ -259,6 +259,6 @@ test("Composer draft with dirty reply can toggle to edit", () => {
   });
   click('.modal-footer a:eq(0)');
   andThen(() => {
-    equal(find('.wmd-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
+    equal(find('.d-editor-input').val().indexOf('This is the first post.'), 0, 'it populates the input with the post text');
   });
 });
diff --git a/test/javascripts/components/d-editor-test.js.es6 b/test/javascripts/components/d-editor-test.js.es6
index 572d7342693..08f3568fdbe 100644
--- a/test/javascripts/components/d-editor-test.js.es6
+++ b/test/javascripts/components/d-editor-test.js.es6
@@ -8,13 +8,10 @@ componentTest('preview updates with markdown', {
 
   test(assert) {
     assert.ok(this.$('.d-editor-button-bar').length);
-    assert.equal(this.$('.d-editor-preview.hidden').length, 1);
-
     fillIn('.d-editor-input', 'hello **world**');
 
     andThen(() => {
       assert.equal(this.get('value'), 'hello **world**');
-      assert.equal(this.$('.d-editor-preview.hidden').length, 0);
       assert.equal(this.$('.d-editor-preview').html().trim(), '<p>hello <strong>world</strong></p>');
     });
   }
diff --git a/test/javascripts/models/composer-test.js.es6 b/test/javascripts/models/composer-test.js.es6
index a31c569caeb..a6c419cf0cb 100644
--- a/test/javascripts/models/composer-test.js.es6
+++ b/test/javascripts/models/composer-test.js.es6
@@ -1,13 +1,10 @@
 import { blank } from 'helpers/qunit-helpers';
 import { currentUser } from 'helpers/qunit-helpers';
-import KeyValueStore from 'discourse/lib/key-value-store';
 import Composer from 'discourse/models/composer';
 import createStore from 'helpers/create-store';
 
 module("model:composer");
 
-const keyValueStore = new KeyValueStore("_test_composer");
-
 function createComposer(opts) {
   opts = opts || {};
   opts.user = opts.user || currentUser();
@@ -185,22 +182,6 @@ test('initial category when uncategorized is not allowed', function() {
   ok(!composer.get('categoryId'), "Uncategorized by default. Must choose a category.");
 });
 
-test('showPreview', function() {
-  const newComposer = function() {
-    return openComposer({action: 'createTopic', draftKey: 'asfd', draftSequence: 1});
-  };
-
-  Discourse.Mobile.mobileView = true;
-  equal(newComposer().get('showPreview'), false, "Don't show preview in mobile view");
-
-  keyValueStore.set({ key: 'composer.showPreview', value: 'true' });
-  equal(newComposer().get('showPreview'), false, "Don't show preview in mobile view even if KeyValueStore wants to");
-  keyValueStore.remove('composer.showPreview');
-
-  Discourse.Mobile.mobileView = false;
-  equal(newComposer().get('showPreview'), true, "Show preview by default in desktop view");
-});
-
 test('open with a quote', function() {
   const quote = '[quote="neil, post:5, topic:413"]\nSimmer down you two.\n[/quote]';
   const newComposer = function() {
diff --git a/test/javascripts/test_helper.js b/test/javascripts/test_helper.js
index cc05265ff78..f75d5d89705 100644
--- a/test/javascripts/test_helper.js
+++ b/test/javascripts/test_helper.js
@@ -21,9 +21,6 @@
 //= require ../../app/assets/javascripts/locales/i18n
 //= require ../../app/assets/javascripts/locales/en
 
-// Pagedown customizations
-//= require ../../app/assets/javascripts/pagedown_custom.js
-
 //= require vendor
 
 //= require htmlparser.js