Prevent reopen tab on closing tabs.

app/assets/javascripts/app/controllers/taskbar_widget.coffee

@@ -81,6 +81,7 @@ class App.TaskbarWidget extends App.Controller
 
   remove: (e, key = false, force = false) =>
     e.preventDefault()
+    e.stopPropagation()
     if !key
       key = $(e.target).parents('a').data('key')
     if !key

app/assets/javascripts/app/lib/app_post/task_manager.coffee

@@ -464,7 +464,6 @@ class _taskManagerSingleton extends App.Controller
     # if task isnt already stored on backend
     return if !task.id
     App.Taskbar.destroy(task.id)
-    return
 
   tasksInitial: =>
     @init()