All face and hat items should be able to have unusual jars applied to them, ones I've noticed you can't are the skull facemask and the santa hat, please can they all be given the flag?
Most of the older facewear won't have unusual effects due to it being decided at the time they should only be applied to hats. I can retroactively go through and make them unusual-enabled though.
Yeah it's a bit confusing which items should and shouldn't have, but Paurice would appreciate on panda glasses
Various items have had the flag added now, mostly face items. There may be some which have been missed - but I think I got most of them.
A player pointed out it can't be applied to the pedobear hat/face item, probably because it goes in 2 slots? Hopefully can be patched.
It looks like this is less of not being allowed but something is going wrong. I can see that it's returning the jar to people when they attempt to unusual-fy it.
Multiple players have reported not being able to apply an effect jar to the Daft Punk helmet. It doesn't return an error, just doesn't apply it, can it be added? Dunno if any other common head items that can be added too.