I've noticed today that when attempting to change the visibility of a log entry, I was no longer able to do so and redirected to Meta-Wiki's Main Page instead.
I started by selecting a log/checkbox here: https://meta.wikimedia.org/wiki/Special:Log/delete and then clicking change visibility.
It then redirects to https://meta.wikimedia.org/w/index.php?action=historysubmit&type=logging&revisiondelete=1&ids%5B28602506%5D=1
Which /should/ have loaded up the form to preform the change.
But instead the link just immediately redirects to https://meta.wikimedia.org/w/index.php?title=Main_Page&action=historysubmit