The startup windows needs window management bars on the top so it can be moved around. It plants itself in the middle of your screen and waits there a LOOOOOONg time waiting to start and can't be minimized off the screen.
Update BepInEx.SplashScreen to v2.2 whenever it is released or wait for the next version of HF Patch. In the meantime you can disable the splash screen in plugin settings.
The startup windows needs window management bars on the top so it can be moved around. It plants itself in the middle of your screen and waits there a LOOOOOONg time waiting to start and can't be minimized off the screen.