help with full screen on slides

I'm really stumped by this. Is the full screen display mode added by a module? If so which one. Why would I be able to enter full screen on my slides on my dev environment but not the live site? I cannot go into full screen mode. On my test environment (local machine) the full screen versions of slides and content work great. But when I transfer or install from scratch on a remote server I do not see the arrow that allow the slide to convert to full screen. Any ideas why? Is it possible it is a setting on the server? Thanks for reading. Any help is greatly appreciated.