PowerShell window popping-up

[Hexaae]

I tried this steamgriddb-manager with Tetris Effect from my Epic Games Launcher list... and it worked fine using the powershell script, it also correctly notified I was playing the game from Steam....
The only problem is that a ps window briefly shows up at launch, while it should be hidden :(

EDIT: another glitch is that once you quit the game, EpicGamesLauncher icon stays in the traybar until mouse hover (abruptly killed task?)

Windows 10