The full screen button and the out of full screen buttons should be the same button located in the same place:
In regular player mode:
Full Screen is the 5th button from the left and
In full screen mode:
Full Screen is right most
The full screen button and the menu buttons have a similar look. It is easy to confuse these two.
https://www.dropbox.com/s/50019wl1bwnmq ... r.png?dl=0
Thanks.