Comment 6 for bug 1413211

P.S. It seems likely that the current implementation of software cursor and touchspots could cause QtMir's compositor to spin and never sleep properly or even hang. This is due QtMir doing:
   src/modules/Unity/Application/mirsurfaceitem.cpp: while (renderable->buffers_ready_for_compositor() > 0) {
which needs to be rewritten quite soon.

I'm working on something that will help us get there:
   https://code.launchpad.net/~vanvugt/mir/fix-buffers_ready_for_compositor/+merge/247124