Comment by Sniffnoy

Facebook does, I'm not sure why it didn't in your case. It adds an "fbclid" parameter that is quite long. I just tried it to confirm.

Edit: Perhaps it only mangles links for logged-in users? That raises the possibility that some of the others may also only affect logged-in users.

(Trying with other ones I'm logged in on: Reddit doesn't mangle (obviously), Twitter doesn't mangle.)