diff --git a/app/assets/javascripts/discourse/components/json-file-uploader.js.es6 b/app/assets/javascripts/discourse/components/json-file-uploader.js.es6
index fc0bf7bd6b2..c86784ca2e7 100644
--- a/app/assets/javascripts/discourse/components/json-file-uploader.js.es6
+++ b/app/assets/javascripts/discourse/components/json-file-uploader.js.es6
@@ -45,7 +45,7 @@ export default Em.Component.extend({
   }.on('didInsertElement'),
 
   accept: function() {
-    return ".json,application/json" + (this.get('extension') ? "," + this.get('extension') : "");
+    return ".json,application/json,application/x-javascript,text/json" + (this.get('extension') ? "," + this.get('extension') : "");
   }.property('extension'),
 
   setReady: function() {
diff --git a/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs b/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
index 3e49a755e5a..6d5d53e5bbf 100644
--- a/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
+++ b/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
@@ -1,6 +1,6 @@
 <form {{action "dummy" on="submit"}}>
   <div class='modal-body'>
-    {{json-file-uploader value=customizationFile extension=".dcstylejson"}}
+    {{json-file-uploader value=customizationFile extension=".dcstyle.json"}}
   </div>
   <div class="modal-footer">
     {{d-button class='btn-primary' action='createCustomization' type='submit' disabled=notReady icon="plus" label='admin.customize.import'}}
diff --git a/app/controllers/admin/site_customizations_controller.rb b/app/controllers/admin/site_customizations_controller.rb
index 0eedc538c41..30929fe4e09 100644
--- a/app/controllers/admin/site_customizations_controller.rb
+++ b/app/controllers/admin/site_customizations_controller.rb
@@ -62,7 +62,7 @@ class Admin::SiteCustomizationsController < Admin::AdminController
       format.any(:html, :text) do
         raise RenderEmpty.new if request.xhr?
 
-        response.headers['Content-Disposition'] = "attachment; filename=#{@site_customization.name.parameterize}.dcstylejson"
+        response.headers['Content-Disposition'] = "attachment; filename=#{@site_customization.name.parameterize}.dcstyle.json"
         response.sending_file = true
         render json: SiteCustomizationSerializer.new(@site_customization)
       end