Ok so after spending 2 full days on this bug, I was able to find my own source for the problem, but I don’t understand why. Wish I had better news for people to save the day, but this is a nasty bug, and the only way to fix it seems to go through every piece of little code you have.
I have a widget called “PlayerWaitingHostStart”
I have a PlayerController called “LobbyPlayerController”
In my “LobbyPlayerController” I made a widget variable called “PlayerWaitingHostStartWB”.
That variable simply existing is what was causing the issue for me.
I deleted the variable. Problem is gone. I re-created the variable. Problem is still gone. I guess I somehow got a corrupted variable?
My only advice to people is to copy your current project, and delete assets 1 by 1 that you worked on last. This will at least help you narrow it down to which blueprint (and you don’t have to worry about ruining or re-creating your project), and hopefully you will remember what you last worked on that could be causing it.