<TabbyCat> have you just updated mediawiki? because popups no longer work for me :/
If blocking the train, it's UBN!
Adding @Prtksxna. Prateek: this showed up during the deploy of wmf.4. It's blocking the train.
Were there any captured error messages/logs with this?
Related to T167222 ?
I'm going to need some more details though... what isn't working exactly? Where can I see this?
Popups are working perfectly fine for me on https://test.wikipedia.org/wiki/Main_Page (navigation popup gadget and popups beta feature). Dropping to normal until I hear otherwise.
https://test.wikipedia.org/wiki/Main_Page is working fine for me too (tested on FF and Chrome on MacOS)
Page Previews (or Popups, Hovercards) are working on cawiki and hewiki (group1) both logged in and logged out. Did TabbyCat mean the NavPopups gadget?
Navigation-Popups-Gadget is a gadget. See its description.
Page-Previews is an extension (nee Hovercards and Popups).
Clarification (and steps to reproduce, which site?) and adjusting the project tag highly welcome.