If you're anything like me you buy games on GOG to get as far away from third-party logins as possible.

So I found a simple way to remove the popup.

* Just go to the game install folder Something like (C:\Program Files\GOG\SpongeBob SquarePants Battle for Bikini Bottom - Rehydrated)

* Then go to the folder "Pineapple\Binaries\Win64\THQNOnline"

* In that folder you will find several other folders and one of them is named "overlay". Just changed that folder's name to anything other than overlay. I just named it "overlayNo".

And that should be it! (Unless they make some dumb patch that makes the game crash on startup if it can't find the overlay folder)

Hope this helped! c:

PS: I believe the login popup has something to do with the Online Multiplayer mode since GOG doesn't have their own default mulitplayer system like steam. So disabling the Overlay might make Online unplayable. If that's the case just rename the folder back to "overlay"

Pretty sure GOG does have its own multiplayer system. Isn't that what GOG Galaxy APIs are mainly for? I also heard it was cross-platform and allowed to be used by other platforms so THQNordic/Purple Lamp could have gone with the Galaxy API for multiplayer instead.

I can't find any actual documentation on this though, it's all hearsay, so please, correct me if this is totally wrong.

I'm no expert either, it's completely possible that GOG Galaxy has their own Multiplayer system. Still though, it looks like Purple Lamp chose Epic Games' multiplayer solution, if not then I have no idea why the popup is even there in the first place.

So I got the physical version of the game (which contains a Steam download key). I wanted to get it on GOG but THQ had confirmed that the GOG version was not cross-play with either Steam or Epic; only Steam and Epic have cross-play as "GOG didn't want that". Post in question: https://steamcommunity.com/app/969990/discussions/0/2516897767697887013/#c2516897767697937490

Maybe you're right and they used Epic's multiplayer system (it's an Unreal Engine game, after all), but in that case I don't understand why I couldn't have been cross-play :/