I noticed this little issue with special:undelete. To reproduce this you have to be admin; if you are on Beta Cluster, you can just go [[https://deployment.wikimedia.beta.wmflabs.org/w/index.php?title=Special:Undelete&target=User%3ADaimona+Eaytoy×tamp=20180607173828|here]] and skip to step 7, otherwise:
# Create a page and make two edits (so that it has 3 revisions)
# Perform a revision delete on the second revision
# Delete the whole page
# Create it again
# Go to the history, then click on "View or restore xxx deleted edits?"
# Click on the version that you previously RevDel'ed
# Check out the message at the top: "This page revision has been deleted. You can view it; details can be found in the deletion log."
# Click on "deletion log"
You should be sent to deletion log for that page, but you are instead sent to deletion log for "Special:Undelete". This is because the revision is shown on Special:Undelete and the involved system message (rev-deleted-text-view) makes use of `{{PAGENAME}}`. The fix shouldn't be hard, but I don't know whether I'll be able to do it myself. BTW, repro steps could possibly be simplified but I didn't even try, since the problem is already quite clear.