This Wednesday, minutes before the server was brought down for the patch, I logged on to check auctions and such. Everything was normal. Later in the day I downloaded the update and logged in. Initially the game window (I play in windowed mode) was tiny; this was probably because I have a 4K monitor and the game was set to display at 1920x1080. So I manually expanded the window to fit my screen. The character load screen looks normal and appropriately scaled, once I'm in game the entire game world is appropriately scaled, but all UI elements are tiny, bordering on unusable. As far as I saw, every single UI element was effected; shortcut bars, buffs, mini-map, party health bars, windows that you might temporarily open such as inventory and social, etc. I looked through graphics and UI settings but didn't see an option to scale UI elements. I tried logging multiple times. I tried windowed, full-screen, and full screen (windowed). I tried letting the settings detect optimal graphics settings. I tried resizing the window by dragging the corner and I tried selecting many window sizes from 1920x1080 through 4096x2160. I think all the settings larger than 1920x1080 are new as of this patch, yes? I've never seen them before, and I think I always had it set to 1920x1080.

Any ideas? (keep in mind, everything worked perfectly right before the patch)

My setup:
Windows 10 (legit copy, up to date)
Intel core i5-3570K
AMD Radeon 7850 (latest stable driver)
16GB DDR3 RAM
Samsung Evo 850 SSD
Samsung 4K tv monitor