Followup for bug 640444. The exact same issue as in that bug, but on Linux Desktop. Bug 640444 comment 12 gives STR and the specific changeset at which this begins.
Continuing the discussion in bug 640444: (In reply to comment #24) > (In reply to comment #22) > > Alon: is your desktop build using --enable-mobile-optimize? If not, can you > > try running with MOZ_LAYERS_FORCE_SHMEM_SURFACES=1 in the environment? > > I don't have --enable-mobile-optimize in my mozconfig. Is that on by default? > > Running with MOZ_LAYERS_FORCE_SHMEM_SURFACES=1 doesn't have any effect. > Building with --enable-mobile-optimize appears to fix things.
This is probably a symptom of bug 594921.