Ok I was slightly wrong about how to reproduce the bug. It's not viewing an item, its clicking the 'appearance' button on the small variant that caused this to happen. Anyway here is that screenshot. (Sorry for the mess I didnt take time to crop it).
Second, I was also able to reproduce the vanishing character window with the described methods. However, logging all the way out of the game and back in did not fix it. Neither did selecting any of the variants from the updater's drop down menu. I did redownload the new default.xml file and placed that in my ui folder and got it to work fine (I Like that the 'default' is very similar to the older style that the window was before this recent update).