Mike's had to do it because Facebook had messed up the way FL interacts with FB.
This is what he posted a few days ago:
Hi everyone - sorry for this issue... I thought it was a temporary FB glitch which would resolve itself, but upon further investigation it seems to be something FB have changed in the way profile pictures work, which means I need to do work to update Fairyland accordingly.
However, this work is unfortunately non-trivial and will take time, so I thought a better alternative might be to instead spend that time switching the game to using everyones "Fairy pictures" as the main in-game pictures. This will be necessary anyway once we move off Facebook (which we have to do next year as Facebook are discontinuing support for games) so it probably makes sense spending the time doing something I'll need to do in a few months time anyway!
Would everyone be happy with this?
Post by Fairyland Developer
Page 4 of this thread:
https://www.fairylandgame.com/fbfairy/forums.php?tid=194769 If you want your own picture to show there, just change your Fairyland fairy picture to the photo you want to show.