diff --git a/app/assets/javascripts/discourse/controllers/topic_controller.js b/app/assets/javascripts/discourse/controllers/topic_controller.js
index 751c15564ea..56b0a663fcb 100644
--- a/app/assets/javascripts/discourse/controllers/topic_controller.js
+++ b/app/assets/javascripts/discourse/controllers/topic_controller.js
@@ -219,6 +219,10 @@ Discourse.TopicController = Discourse.ObjectController.extend(Discourse.Selected
 
   },
 
+  slackRatio: function() {
+    return Discourse.Capabilities.currentProp('slackRatio');
+  }.property(),
+
   jumpTopDisabled: function() {
     return (this.get('progressPosition') <= 3);
   }.property('progressPosition'),
diff --git a/app/assets/javascripts/discourse/templates/topic.js.handlebars b/app/assets/javascripts/discourse/templates/topic.js.handlebars
index bd910af6a16..b785637b65f 100644
--- a/app/assets/javascripts/discourse/templates/topic.js.handlebars
+++ b/app/assets/javascripts/discourse/templates/topic.js.handlebars
@@ -64,7 +64,7 @@
           {{/if}}
 
           {{#unless postStream.loadingFilter}}
-            {{cloaked-collection cloakView="post" idProperty="post_number" defaultHeight="200" content=postStream.posts}}
+            {{cloaked-collection cloakView="post" idProperty="post_number" defaultHeight="200" content=postStream.posts slackRatio=slackRatio}}
           {{/unless}}
 
           {{#if postStream.loadingBelow}}