use FB disconnect, noscript and ublock, use multiple container profiles (not just for FB).

I've quit FB, but the above might be enough to contain FB for those who can't/won't. I still do the above for any other privacy-hating aspirants.

Not saying you shouldn't play the cat and mouse game but it wouldn't take much to have the FB code served first party.

You're gaining security the same way bike locks provide security. Anyone motivated could break it but you're hoping that enough people are easier targets that you're ignored.

This solution is good for you personally but it's not a fix.