Not sure if glitch or feature.

Whenever a player disconnects from my server their props are automatically removed after a brief period of time. I can see how it might be useful for an unmoderated server, but for me and my friends it’s a pain in the ass. Is this a default feature of Garrysmod and can I turn it off? I’m thinking it might also be part of ASS mod which is my preferred admin tool, but I can’t find any option that auto deletes props from disconnected users. Any ideas?

It’s a part of your admin mod.

Utilities > Falco’s Prop Protection > Admin Settings > General Options, and then turn off “cleanup disconnected players entities”

Falco’s Prop Protection doesn’t appear anywhere in the utilities tab.

If I remember correctly, and it’s been a decent few years since I hosted GMod, but it’s a feature of Simple Prop Protection (one of the oldest prop protection mods).

I haven’t thoroughly used the updated ASSMod on Workshop, so I can’t tell you if it was included with it.

This doesn’t come with Garry’s Mod (unless he added it the last days)
What addons do you have installed?

The only addon that would be related would be ASSmod.