Possibly some addon.
Something similar happened to me on patch day, disabling some addons it got fixed.
But they've been updated now and everything works again.
Update your addons and try disabling some of them
lordrichter wrote: »I am going with add-on induced game bug.
I have seen something similar to this, usually when logging into a character for the first time on a particular day. Logging out and logging back in fixes it for me, which makes it impossible to quickly tell what add-on (if any) is causing the problem.
I do know that, for me, it started while running only add-ons that had been updated for Update 17. This time, though, not all of the add-ons claiming to be updated for 17 were actually working with the update.
wait, they have a UI problem and havent disabled a ui addon?
EDIT: So he took out all addons and tested each one, turns out it's Dark UI that's causing all the trouble.
VexingArcanist wrote: »There is a "community" option in Dark UI, I think it's called "Smoother Backgrounds". This is your culprit. Untick it.
The problem with DarkUI is many of the elements do not unload unless you relaunch the game, so disabling addons but not closing the cliet will not resolve the issue ... until you relaunch the client.