Comment # 28 on bug 1135237 from Peter S�tterlin

So I had a look at it again (thanks for kicking my back ;^>)

The systems are on Tumbleweed 20200414 (wanted to do an update before, but I
first have to look closer at the Python2 removal this would cause), so this is
with MESA 20.0.4.

The issue is still there.  I think the CPU load cause by the X server is
reduced a bit, it now typically is between 35 and 75 percent, but the lags in
screen updates are still there.

If you want me to try some stuff, I should be able to do so now.