You cannot use the same root element (#ember-testing) multiple times in an Ember.Application

[sajt]

I get the following errors in a lot of Integration and acceptance tests:
Error: Assertion Failed: You cannot use the same root element (#ember-testing) multiple times in an Ember.Application
and
Promise rejected before it renders: Assertion Failed: You cannot use the same root element (#ember-testing) multiple times in an Ember.Application

My tests now is what the ember g generated, I do not changed anything on it.

[sajt]

I think here is the solution: emberjs/ember.js#11738

[sajt]

No. I upgraded my all project to Ember 2 and everything is the latest version (I hope...) but I got the same error.

[trentmwillis]

@sajt that usually means an earlier test didn't clean up properly (usually due to an error being thrown).

[sajt]

Now it is working, but I do not know why :)