diff --git a/app/assets/javascripts/discourse/components/expand-post.js.es6 b/app/assets/javascripts/discourse/components/expand-post.js.es6
new file mode 100644
index 00000000000..957750e92f2
--- /dev/null
+++ b/app/assets/javascripts/discourse/components/expand-post.js.es6
@@ -0,0 +1,19 @@
+import { ajax } from 'discourse/lib/ajax';
+
+export default Ember.Component.extend({
+  tagName: '',
+
+  actions: {
+    expandItem() {
+      const item = this.get('item');
+      const topicId = item.get('topic_id');
+      const postNumber = item.get('post_number');
+
+      return ajax(`/posts/by_number/${topicId}/${postNumber}.json`).then(result => {
+        item.set('truncated', false);
+        item.set('excerpt', result.cooked);
+      });
+    }
+  }
+});
+
diff --git a/app/assets/javascripts/discourse/components/stream-item.js.es6 b/app/assets/javascripts/discourse/components/stream-item.js.es6
index e205f50a3f5..26d1e6f8e5a 100644
--- a/app/assets/javascripts/discourse/components/stream-item.js.es6
+++ b/app/assets/javascripts/discourse/components/stream-item.js.es6
@@ -1,22 +1,8 @@
 import { propertyEqual } from 'discourse/lib/computed';
 import { actionDescription } from "discourse/components/small-action";
-import { ajax } from 'discourse/lib/ajax';
 
 export default Ember.Component.extend({
   classNameBindings: [":item", "item.hidden", "item.deleted:deleted", "moderatorAction"],
   moderatorAction: propertyEqual("item.post_type", "site.post_types.moderator_action"),
   actionDescription: actionDescription("item.action_code", "item.created_at", "item.username"),
-
-  actions: {
-    expandItem() {
-      const item = this.get('item');
-      const topicId = item.get('topic_id');
-      const postNumber = item.get('post_number');
-
-      return ajax(`/posts/by_number/${topicId}/${postNumber}.json`).then(result => {
-        item.set('truncated', false);
-        item.set('excerpt', result.cooked);
-      });
-    }
-  }
 });
diff --git a/app/assets/javascripts/discourse/templates/components/expand-post.hbs b/app/assets/javascripts/discourse/templates/components/expand-post.hbs
new file mode 100644
index 00000000000..4d3192668d1
--- /dev/null
+++ b/app/assets/javascripts/discourse/templates/components/expand-post.hbs
@@ -0,0 +1,5 @@
+{{#if item.truncated}}
+  <a class="expand-item" href {{action "expandItem"}} title={{i18n "post.expand_collapse"}}>
+    {{fa-icon "chevron-down"}}
+  </a>
+{{/if}}
diff --git a/app/assets/javascripts/discourse/templates/components/group-post.hbs b/app/assets/javascripts/discourse/templates/components/group-post.hbs
index 09ac259ce27..bd7f867e86f 100644
--- a/app/assets/javascripts/discourse/templates/components/group-post.hbs
+++ b/app/assets/javascripts/discourse/templates/components/group-post.hbs
@@ -2,6 +2,7 @@
   <div class='clearfix info'>
     <a href="{{unbound post.user.userUrl}}" data-user-card="{{unbound post.user.username}}" class='avatar-link'><div class='avatar-wrapper'>{{avatar post.user imageSize="large" extraClasses="actor" ignoreTitle="true"}}</div></a>
     <span class='time'>{{format-date post.created_at leaveAgo="true"}}</span>
+    {{expand-post item=post}}
     <span class="title">
       <a href={{post.url}}>{{{post.topic.fancyTitle}}}</a>
     </span>
@@ -13,6 +14,6 @@
     </div>
   </div>
   <p class='excerpt'>
-  {{{unbound post.excerpt}}}
+  {{{post.excerpt}}}
   </p>
 </div>
diff --git a/app/assets/javascripts/discourse/templates/components/stream-item.hbs b/app/assets/javascripts/discourse/templates/components/stream-item.hbs
index 71c2bb9e333..ea3c9dcec98 100644
--- a/app/assets/javascripts/discourse/templates/components/stream-item.hbs
+++ b/app/assets/javascripts/discourse/templates/components/stream-item.hbs
@@ -1,11 +1,7 @@
 <div class='clearfix info'>
   <a href={{item.userUrl}} data-user-card={{item.username}} class='avatar-link'><div class='avatar-wrapper'>{{avatar item imageSize="large" extraClasses="actor" ignoreTitle="true"}}</div></a>
   <span class='time'>{{format-date item.created_at}}</span>
-  {{#if item.truncated}}
-    <a class="expand-item" href {{action "expandItem"}} title={{i18n "post.expand_collapse"}}>
-      {{fa-icon "chevron-down"}}
-    </a>
-  {{/if}}
+  {{expand-post item=item}}
   {{topic-status topic=item disableActions=true}}
   <span class="title">
     <a href={{item.postUrl}}>{{{item.title}}}</a>
diff --git a/app/serializers/admin_user_action_serializer.rb b/app/serializers/admin_user_action_serializer.rb
index 6d776de23dc..0cc58aa27a6 100644
--- a/app/serializers/admin_user_action_serializer.rb
+++ b/app/serializers/admin_user_action_serializer.rb
@@ -1,4 +1,7 @@
+require_relative 'post_item_excerpt'
+
 class AdminUserActionSerializer < ApplicationSerializer
+  include PostItemExcerpt
 
   attributes(
     :id,
@@ -13,7 +16,6 @@ class AdminUserActionSerializer < ApplicationSerializer
     :title,
     :category_id,
     :truncated,
-    :excerpt,
     :hidden,
     :moderator_action,
     :deleted,
@@ -23,18 +25,10 @@ class AdminUserActionSerializer < ApplicationSerializer
     :action_type
   )
 
-  def truncated
-    true
-  end
-
   def post_id
     object.id
   end
 
-  def include_truncated?
-    object.excerpt != object.cooked
-  end
-
   def deleted
     deleted_at.present?
   end
diff --git a/app/serializers/group_post_serializer.rb b/app/serializers/group_post_serializer.rb
index 1fb6305e59a..99a06f55340 100644
--- a/app/serializers/group_post_serializer.rb
+++ b/app/serializers/group_post_serializer.rb
@@ -1,10 +1,15 @@
+require_relative 'post_item_excerpt'
+
 class GroupPostSerializer < ApplicationSerializer
+  include PostItemExcerpt
+
   attributes :id,
-             :excerpt,
              :created_at,
              :title,
              :url,
-             :category
+             :category,
+             :post_number,
+             :topic_id
 
   has_one :user, serializer: GroupPostUserSerializer, embed: :object
   has_one :topic, serializer: BasicTopicSerializer, embed: :object
diff --git a/app/serializers/post_item_excerpt.rb b/app/serializers/post_item_excerpt.rb
new file mode 100644
index 00000000000..be74db9bdf9
--- /dev/null
+++ b/app/serializers/post_item_excerpt.rb
@@ -0,0 +1,25 @@
+module PostItemExcerpt
+
+  def self.included(base)
+    base.attributes(:excerpt, :truncated)
+  end
+
+  def cooked
+    @cooked ||= object.cooked || PrettyText.cook(object.raw)
+  end
+
+  def excerpt
+    return nil unless cooked
+    @excerpt ||= PrettyText.excerpt(cooked, 300, keep_emoji_images: true)
+  end
+
+  def truncated
+    true
+  end
+
+  def include_truncated?
+    cooked.length > 300
+  end
+
+end
+
diff --git a/app/serializers/user_action_serializer.rb b/app/serializers/user_action_serializer.rb
index 2db30ca9077..81b2cb2fe60 100644
--- a/app/serializers/user_action_serializer.rb
+++ b/app/serializers/user_action_serializer.rb
@@ -1,9 +1,10 @@
+require_relative 'post_item_excerpt'
+
 class UserActionSerializer < ApplicationSerializer
+  include PostItemExcerpt
 
   attributes :action_type,
              :created_at,
-             :excerpt,
-             :truncated,
              :avatar_template,
              :acting_avatar_template,
              :slug,
@@ -30,22 +31,6 @@ class UserActionSerializer < ApplicationSerializer
              :closed,
              :archived
 
-  def cooked
-    @cooked ||= object.cooked || PrettyText.cook(object.raw)
-  end
-
-  def excerpt
-    return nil unless cooked
-    @excerpt ||= PrettyText.excerpt(cooked, 300, keep_emoji_images: true)
-  end
-
-  def truncated
-    true
-  end
-
-  def include_truncated?
-    cooked.length > 300
-  end
 
   def avatar_template
     User.avatar_template(object.username, object.uploaded_avatar_id)