I think this might be caused by the fix for bug 1036587:
if (doShellRepaint && !force && fullscreenRegion.contains(*output))
doShellRepaint = false;
#ifndef USE_MODERN_COMPIZ_GL
if (doShellRepaint)
paintDisplay(region, transform, mask);
#endif
For example, with a fullscreen window on the last output, doShellRepaint becomes false and the shell doesn't get drawn at all. Because that happens in UnityScreen::glPaintCompositedOutput now.
I think this might be caused by the fix for bug 1036587:
if (doShellRepaint && !force && fullscreenRegio n.contains( *output) )
doShellRepaint = false;
#ifndef USE_MODERN_ COMPIZ_ GL y(region, transform, mask);
if (doShellRepaint)
paintDispla
#endif
For example, with a fullscreen window on the last output, doShellRepaint becomes false and the shell doesn't get drawn at all. Because that happens in UnityScreen: :glPaintComposi tedOutput now.