It looks like I'll be relying on XDA Labs for the near future. Because the developers behind XDA Developers broke something that really didn't need fixing. Quick access to notifications and PMs, quick access to my various devices? All wiped out and replaced by a hamburger menu with only three options. Heck, I can't even sign out of XDA using this updated theme even if I wanted to.
This is a bust. For the time being, until you ruin it by fixing things that don't need fixing, I've reverted to the 2013 theme. I may not have quick access to my devices, but I can at least see my notifications as intended, and I don't have to deal with caching issues.