@jerry before I left a number of years ago, I saw all kinds of context added and general moderation/censorship, but it was awful. It was either super automated or run by idiots. You'd be sarcastically mocking an idea and you'd get hit as if you were the one spreading it. I think 95% of their fact checks missed the point.
Somebody would post a scientific study contrasting different kinds of masks and their efficacy and FB would do things like plaster over it with a braindead fact check generally asserting masks are good. Then they censored a bunch of true things, but overall it essentially ended up picking the most annoying undergrad students to spam their misunderstandings over regex matched posts globally.
I won't miss it.