And... now it's not working again. Can you clarify exactly how tkinter finds tk/tcl? Does it rely on TCL_LIBRARY or TK_LIBRARY env vars? TCLLIBPATH? If I use all of these env vars, tkinter finds tcl/tk, but commands like:

$ python -m tkinter
$ python -c 'import tkinter; tkinter._test()'

open a window and immediately minimize it. If I try to maximize the window it immediately closes, so something is definitely wrong with my installation.