This relates to the permissions tab under Special:ManageWiki
I edited the .css for that via MediaWiki:Timeless.css and now it won't show the dropdown box upon trying to add new sites to the white list, it only allows editing via text, the bar on the bottom showing loading stripes, clicking the loading stripes doesn't do anything,
I did revert the .css changes but that didn't do much, sometimes it would change back to the normal drop down menu but either changing to a sub menu or refreshing the page reverts it to text, and even with the .css changes, it sometimes shows the text box but sometimes shows the actual drop down menu.
This is something that only affects $wmgWhitelistRead, none of the other drop down menus on Special:ManageWiki are affected. I've tested it via both private browsing, two different browsers, and via adding " ?safemode=1 " to the end of the url, but the issue persists through all of these. I manage three wikis and this happens on all three so I have no idea what could be causing the issue., .css shouldn't be a cause for the issue anyway especially since that's all i changed there.
The affected wikis, I have no idea if it's just a random breakage or if there's anything i need to do to fix that, poking around with inspect element didn't yield many conclusive results.