How to keep my Gmod clean now? (removing unnecesarry files after addon deletion)

[Kethus]

So Gmod, like other source games lately, started using some new format. How are addons stored now? I see there is a "garrysmod_old" folder. I've deleted most addons from the addon folder there, but they still remain, where are they stored now (hope it's not somewhere in the C:/ drive)? Does the game automatically erase files of uninstalled addons now?

[c👌de_g🎷]

Look in your common folder, not (username).