diff --git a/app/assets/javascripts/discourse/dialects/quote_dialect.js b/app/assets/javascripts/discourse/dialects/quote_dialect.js
index 3c50598cfcb..28f8de131cb 100644
--- a/app/assets/javascripts/discourse/dialects/quote_dialect.js
+++ b/app/assets/javascripts/discourse/dialects/quote_dialect.js
@@ -26,7 +26,9 @@ Discourse.BBCode.register('quote', {noWrap: true, singlePara: true}, function(co
   if (options.lookupAvatarByPostNumber) {
     // client-side, we can retrieve the avatar from the post
     var postNumber = parseInt(params['data-post'], 10);
-    avatarImg = options.lookupAvatarByPostNumber(postNumber);
+    var topicId = parseInt(params['data-topic'], 10);
+
+    avatarImg = options.lookupAvatarByPostNumber(postNumber, topicId);
   } else if (options.lookupAvatar) {
     // server-side, we need to lookup the avatar from the username
     avatarImg = options.lookupAvatar(username);
diff --git a/app/assets/javascripts/discourse/views/composer.js.es6 b/app/assets/javascripts/discourse/views/composer.js.es6
index 8a4050bc033..6c3047ba8f8 100644
--- a/app/assets/javascripts/discourse/views/composer.js.es6
+++ b/app/assets/javascripts/discourse/views/composer.js.es6
@@ -260,9 +260,9 @@ const ComposerView = Discourse.View.extend(Ember.Evented, {
 
     this.editor = editor = Discourse.Markdown.createEditor({
       containerElement: this.element,
-      lookupAvatarByPostNumber(postNumber) {
+      lookupAvatarByPostNumber(postNumber, topicId) {
         const posts = self.get('controller.controllers.topic.model.postStream.posts');
-        if (posts) {
+        if (posts && topicId === self.get('controller.controllers.topic.model.id')) {
           const quotedPost = posts.findProperty("post_number", postNumber);
           if (quotedPost) {
             const username = quotedPost.get('username'),