I can’t re-enter SC2 once I tab out. I tried using the Alt-Tab shortcut, or just clicking the window in my taskbar. None of those options works. The screen just flickers briefly before going back to whatever non-SC2 window that I already had open.
The only way I found to get around this is by using the Bnet Launcher and selecting “Play” on the SC2 launcher page. This works, but it’s kind of a pain. I’d rather just tab back in as usual.
I didn’t change any relevant settings recently, whether in SC2, Bnet, or on my computer.
I’m using Windows 10 (64 bit) on a Razer Blade 15 laptop.
Edit: It was definitely my computer’s fault. Every other fullscreen game had the exact same problem. I fixed it by using Windowed Fullscreen mode instead of using actual Fullscreen. I may never know what caused this issue, but at least I have a permanent solution.