@jackie_w:
* Good point, the fact that it doesn't draw a background *at all* means that this sort of thing can indeed happen, yeah

.
* That may be a side-effect of how night-mode actually inverts the screen. With a software nightmode, it would work, but if it relies on the controller's inversion (which I *think* the latest versions do), I indeed have no idea how it might work, but probably not well ;p. And if the hack somehow manages to hook into fbink's own refresh calls, that's one more layer of unknown

.
(But given the fact that you mention a white rectangle, I'm guessing the hack doesn't touch fbink's calls, and that rectangle is the refresh region itself, not getting inverted because fbink never does that).
That's what you get for weird 5AM ideas, I guess, sorry ;p.