[blaze33]

Yes, lots of people have at least some of their photos only stored on FB and have no backups, so FB ends up being their de facto "photo backup service".

Obviously you should routinely backup your data, yet here we are. Last year I noticed that most of the photo albums I shared on FB over the years just disappeared. They were not hidden by some app setting, nor temporarily unavailable, the data dump FB offers has no trace they even ever existed. The data was gone. I reported the issue but never got any answer. Thankfully I had the original photos on my old desktop. So when your data may randomly vanish, do backups, just my two cents.