Yes. As long as your images and yours are online on meta, you've transferred the copyright to them.
https://files.mastodon.social/media_attachments/files/114/154/672/392/077/332/original/8fb529c1aa14004b.jpg
my migration campaign on meta.
(addition: forgive my poor english, as some guys pointed out: You do not give Facebook the copyright to your posts. You give them a license to your content.
however you call it, I'd say.)
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