I think there is a an issue between template actions and event in components.
As far as I understand all action clicks will be first executed and bubbled. Then events in components will be. There are like two parallel stacks executed one after the other.
If you have something like this in the template of a component:
Hello <button onclick={{action ‘firstMessage’}}>Click me
and this in the corresponding javascript file:
click: function() { alert(‘second message’); }
You are not sure that the second message will be displayed. If event.stopPropagation() is called in the stack of action, the it will not.
Here is a twiddle: Ember Twiddle