Fixed not shown activity stream.

app/assets/javascripts/app/controllers/_dashboard/activity_stream.coffee

@@ -41,12 +41,10 @@ class App.DashboardActivityStream extends App.Controller
   render: (items) ->
 
     # show description of activity stream
-    if _.isEmpty(items)
-      @$('.activity-description').removeClass('hidden')
-      return
+    return if _.isEmpty(items)
 
     # remove description of activity stream
-    @$('.activity-description').remove()
+    @$('.activity-description').removeClass('activity-description')
 
     items = @prepareForObjectList(items)
 
@@ -54,8 +52,7 @@ class App.DashboardActivityStream extends App.Controller
     for item in items
       html.append(@renderItem(item))
 
-    @$('.activity-entries').remove()
-    @el.append html
+    @el.html html
 
   renderItem: (item) ->
     html = $(App.view('dashboard/activity_stream')(

app/assets/javascripts/app/controllers/dashboard.coffee

@@ -33,7 +33,7 @@ class App.Dashboard extends App.Controller
     )
 
     new App.DashboardActivityStream(
-      el:    localEl.find('.sidebar')
+      el:    localEl.find('.js-activityContent')
       limit: 25
     )
 

app/assets/javascripts/app/views/dashboard.jst.eco

@@ -8,7 +8,7 @@
 </div>
 <div class="sidebar optional">
   <h2><%- @T('Activity Stream') %></h2>
-  <div class="activity-description hidden">
+  <div class="activity-description js-activityContent">
     <p><%- @T('Here you will find latest activities in your system.') %></p>
     <p><%- @T('E. g. recent changed tickets, users or organizations.') %></p>
   </div>