A bug with fullscreen mode

Bug Report
1

I have a common bug with Overwatch. I have set the game to fullscreen mode. But often, when I start the game, it starts in windowed mode and I have to go to the settings to change it again. I’m not sure what causes it, and don’t know the solution. If you are experiencing this issue or know the solution, tell me. Thanks.

2

Yep. Sometimes it happens (Win 10). It started a few days ago.
I just press Alt + Enter to switch fullscreen, when it happens again.

I don’t know, but you can try to Repair the game files and Reset options via Blizzard app.