For the last few days my GOG Galaxy hasn't been able to see that I have any Steam games installed. It's logged in, and it shows all the games on my Steam account, but nothing shows up as installed, even though they are. There is an Install button on the relevant game pages that brings up "Please wait, we are launching Steam" but then that leads to nothing happening. I've tried reconnecting the account, syncing integrations, even reinstalling GOG Galaxy completely, but to no avail.

The only other thing that's changed is I recently got a new hard drive which I moved some of the Steam games onto, but Steam keeps track of all that, so as far as I know it should just work right?

Anyone have any ideas?

No worries actually, fixed it. I found I had the same problem in Playnite, so I reinstalled Steam instead and that worked.

How does that make sense? And I sure as hell won't reinstall STEAM to make Galaxy work, since I can launch those games through Steam (non-reinstalled) perfectly fine. Either Galaxy gets a fix, or it's dead (it largely is, because it lacks the most important trait: STABILITY).

Don't know the technical details or anything, but I assume something went wrong with Steam's installation that made other programs (not just Galaxy, so probably isn't GOG's fault) unable to interface with its local library, or something. Either way reinstalling Steam worked. It wasn't a big deal, it's not like you lose all your installed games or anything, just make sure your steamapps folder is in a safe place outside the steam folder before uninstalling and its fine.