Comment # 137 on bug 1112824 from Victor Zhestkov

Simon, I agree with you it's not just a kernel issue. And Dead Mozay said it's
quite complicated. I've tried to analyze, but not yet get a full view.
But basically speaking - there are a lot of issues inside GNOME (gjs,
gnome-shell and probably mutter are affected), but these issues become more
visible with kernel issue. spectre_v2=retpoline boot option really helps, but
some lags still there.
Finally I gave up with tumbleweed, there are too many packages updated the same
time and it makes it harder to find out the exact root cause, especially
because as I said I'm sure it's not only one issue.
I just finished building some packages related to GNOME with the fixes I think
should help, but I did it for Leap 15 and still testing it. Leap 15 has
different issues in GNOME, but it seems easier to fix.
For example one of the patch fixing tweener.js errors in journal, not just
suppressing the messages as it was done with gdm options in some builds, but
really fix the behavior of using objects. I'm still testing on my system, but
if somebody wants to check it too, I'll be happy. But please note, the fixes is
for Leap 15.0 only.