WowAce

with patch 7.2.5 the Possess bar's buttons (when you get into a vehicle) became non-responsive for keyboard button press. (1-2-3, etc)

Not only that, but the bar is actually missing from the screen as well. I've had this issue occur when doing the Felsoul Hold Suramar WQ daily when shooting from cannons and also from the Aquaclease WQs on the Broken Shore.

The whole "Blizzard Vehicle UI" is broken. It's invisible and keybinds are not responsive.

same problem, get into a vehicle, and i have to use keybinds or mouse clicks to use the vehicle abil's, and also having problem with stealth staying on for 2-5sec after opening attack to break stealth as a rogue.

This is unfortunately a Blizzard bug. Even with default UI the vehicle UI doesn't come up on some world quests.

Same as above, the Blizzard Vehicle Bar doesn't show up.

I don't know if it's a Blizzard bug, but if I stay in the vehicle, go in my addons settings and remove Bartender from my enabled addon, the UI reload and then the Blizzard Bar is correcly displayed.

The issue would also resolve itself if you would just reload the UI without disabling Bartender. The UI doesn't send the appropriate events to show the vehicle interface, but once you reload it does.