Interesting. I always leave the CALIBRE_DEVELOP_FROM environment variable set up, but I point it to a non-existent dummy folder ".../calibre/srcjunk" instead of ".../calibre/src" within my calibre source repo... basically because I'm lazy and don't want to setup the environment variable from scratch each and every time.
To make a long story short... it was using the defaults_tweaks.py file from the ".../calibre" folder of my source repo. Deleting the environment variable fixed it. I didn't realize any of the parent directories of the CALIBRE_DEVELOP_FROM env var were in play. I wasn't running from src or anything... the asterisk wasn't showing up in the GUI before I upgraded, anyway. Oh well.
Anyway, thanks for pointing me in the right direction.
