How do I add anti piracy measures to my game?
Force the user to login via firebase is probably the most universal way. It drastically depends on how you sell your game. The itch.io APIs to check whether the user owns the game only works when using the itch.io app to launch the game. Steam APIs require building the product manually with greenworks (which is not easy, but is doable).
However, your instincts are probably wrong if you are worried about piracy. Instead focus all your time and energy worrying about lost profits into marketing… it will pay off a lot more.
You probably shouldn’t worry about that. Maybe people pirated games a lot back in the 90s and 2000s but pretty sure that these days only games that are really popular get pirated.
Are you referring to an anti piracy screen?, You can get the current URL via the url tools extension and switch to an anti piracy scene if it is not one you uploaded the game to.