It looks like you have to delete the old stale fork relationship first,
otherwise you will end up with a 409 Conflict error ("Project already
forked").
To automate fixing the fork status without requiring creation of an
access token, I wrote a small script that can be executed from your web
browser. See https://gitlab.com/wireshark/wireshark/-/issues/16806
My wireshark repo on gitlab is not a fork of the main one (I've created it much earlier). Do you think the fork status can be forced on it as well? Just out of curiosity, I've already re-forked.
