Chrome Version       : 48.0.2564.116
OS Version: 
URLs (if applicable) :
Other browsers tested:
  Add OK or FAIL after other browsers where you have tested this issue:
  Chrome app, not applicable
     Safari 5:
  Firefox 4.x:
     IE 7/8/9:

What steps will reproduce the problem?
1. ???
2. Choose Apps from the toolbar
3. Choose Hangouts
4. Switch to other window
5. Hangouts is not in the list of alt-tab windows nor in the list of Chrome windows, nor in the list of open apps.

The problem seems to be intermittent, i.e. I can now see the Hangouts window in the lists. However, the problem persisted while I repeated going to Apps - Hangouts route. I did not restart Chrome.

What is the expected result?
That alt-tabbing gets me back to Hangouts window.

What happens instead of that?
Lack of window changing options.

Please provide any additional information below. Attach a screenshot if
possible.

UserAgentString: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/48.0.2564.116 Safari/537.36

Ubuntu 14.04 LTS.