Paint List is often full of 1x1 offscreen windows from gtk-window-decorator

Debugging PrivateGLScreen::paintOutputRegion, I find my paint list is often full of 1x1 off-screen windows from gtk-window-decorator. Surely we should be ignoring these in the paint loop(s) for efficiency?

win 0: 14001ef gtk-window-decorator 1x1 +-100+-100, draw=Y
win 1: 14001ec gtk-window-decorator 1x1 +-100+-100, draw=n
win 2: 140019b gtk-window-decorator 1x1 +-100+-100, draw=Y
win 3: 1400198 gtk-window-decorator 1x1 +-100+-100, draw=n
win 4: 1400147 gtk-window-decorator 1x1 +-100+-100, draw=Y
win 5: 1400144 gtk-window-decorator 1x1 +-100+-100, draw=n
win 6: 14000f3 gtk-window-decorator 1x1 +-100+-100, draw=Y
win 7: 14000f0 gtk-window-decorator 1x1 +-100+-100, draw=n
win 8: 1400092 gtk-window-decorator 1x1 +-100+-100, draw=Y
win 9: 140008f gtk-window-decorator 1x1 +-100+-100, draw=n
win 10: 140007d gtk-window-decorator 1x1 +-100+-100, draw=Y
win 11: 140007a gtk-window-decorator 1x1 +-100+-100, draw=n
win 12: 1400049 gtk-window-decorator 1x1 +-100+-100, draw=Y
win 13: 1400026 gtk-window-decorator 1x1 +-100+-100, draw=n