Guild window bug since Phase 2 patch - UI taint?

I'm getting the error "Tukui has been blocked from an action only available to the Blizzard UI. You can disable this addon and reload the UI. [Disable] [Ignore]". Sometimes it triggers immediately upon opening the guild window, sometimes it triggers the moment I mouse over the guild window frame, and sometimes it's only triggered when I edit (and accept) the guild message of the day. I am able to reproduce the issue with only Tukui enabled, no other mods.