I reported a bug on the fedora bugzilla quite a while ago, but no one has responded. I told myself that it might be more appropriate to put it here. So, here is the link:
The HW cursor fails and is replaced by a swcursor (due to an issue in the display hardware) that is being mishandled by the compositor. The delay in rendering is due to a bug in mesa.
To avoid the swcursor fallback, don't use pipe 2. Something like "xrandr --output HDMI2 --preferred --pipe 0" should do the trick. Still bizarre that an earlier application chose to configure it on pipe 2.
$ xrandr --output HDMI2 --preferred --pipe 0
xrandr: unrecognized option '--pipe'
(In reply to presidentnotsure.eo from comment #3)
> $ xrandr --output HDMI2 --preferred --pipe 0
> xrandr: unrecognized option '--pipe'
The option would be '--crtc 0'. Unfortunately it's not going to help because only pipe C (ie. crtc 2) can drive the HDMI output (port D).