*.wikimedia.org doesn't have SUL autologin globally because of all the various services we host on that domain. But we should add the permanent wikimania.wikimedia.org wiki to it.
So, I synced this patch per @Zabe's request. However, I tried to autolog in to wikimania.wikimedia.org before the deployment (using my WMF staff account, as the volunteer acc was already logged in, and also in inkognito window with a test acc), and it _worked_. Are we sure it's not just enabled everywhere? cc @Legoktm.
Ummm, well it didn't work when I filed this task. I can't explain why it would've worked, unless I missed some change to SUL.
In any case, I logged into Meta just now (using private browsing) and it made the following requests:
Then I went to wikimania.wikimedia.org and it popped up the "You've been centrally logged in, please refresh the page" bubble notification and I was logged in (I thought I would already be logged in without the need for refresh but meh).