I can't tab back into my game

Occasionally, when I tab out of MCC, the game will become a background app, and it wont let me re-open it again, even though I still hear it in the background. Does this happen to anyone else? Is there some work around that lets me open it up again?

Yes, there’s a fairly long thread on here about this issue: ‘ALT+TAB CAUSING GAME TO DISAPPEAR, NOT CRASH’ from memory, there are a couple of suggestions on how to prevent the issue (virtual desktop settings in Windows and using borderless mode in the game).