We have a client using Firefox 35.0.3.  When she opens a new mail, it always opens in full screen.  When she replies to a mail it opens in full screen.  (When she uses Chrome, it opens as a smaller window.)  She indicated that this is a new behavior.  On her computer, it used to open/reply to emails in as a smaller window.

 

I have Firefox 35.0.2 and it opens emails in the smaller window.

 

Is anyone else seeing this behavior.  It must be something with the browser.  Any ideas are appreciated.