I watch a YouTube video in full screen mode. I turn the phone sideways to fill the screen. When I turn the phone back up right I get a consistent problem. I see half of the full screen. I see the left side of the screen and I can't scroll over to the right side of the screen to change tabs. So I'm stuck. I have updated and reinstalled Firefox several times. Imagine your screen shows half of a full screen. It's always the left half. If I turn my phone back horizontal then I see everything. But when I turn my phone back up right it doesn't leave full screen mode. Instead it shows me half of full screen mode. Thanks for your assistance.