VERY minor bug, but thought I'd report it anyways.As shown in the GIF:
If you're in the city view and have a building window open.
If you then click where the back button usually is, right at the edge of the game.
You'll actually hit the invisible back button and it'll quickly load the shop, then open up the city view again with the building panel open.
Once you close window you'll be in your shop and the inventory & energy bar and a few other UI elements is gone.
It's quickly regained by entering inn/city and going back again.