Comment 40 for bug 1870736

I am not familiar with code, so I just test what I could see... hope it helps (I posted also on bug 1873403, if not necessary I'll remove it. No intention to spam).

------------not live: tests as I remember:
without nvidia
100-->ok
125,150 too slow

with nvidia
100--> too small
200-->too big
enable fractional scaling
125-->200
150-->200
175 -->black
(stop/start freesync from monitor, restored - maybe random behavior)

2nd try
100-->ok
125-->black
(couldn't restore it, ctrl+alt+f1 & login = black again)

unistall nvidia tested drivers, try nouveau
after two changes, I could see ubuntu desktop became small or big inside my screen and around it I cound draw with the window I was holding with the mouse. If I put it inside ubuntu desktop area of my screen it works fine, outside (right column and down line) it just performs like windows xp windows when it stuck (never saw it again on ubuntu since 11.10 that I am using it).

------------live: test and keep these notes:
install nvidia again
reboot - 3rd try
100--> bigger desktop than my screen, needs to scroll (down or right) to see the rest
200--> the same
enable fractional scaling (returns to 100 by itself)
150-->black
(stop/start freesync from monitor, restored - maybe random behavior)

100 --> enable fractional-->200 by itself
I repeat it, doesn't happen the second time
150-->black

remove nvidia* through synaptic
reboot
100-->ok
125,150,175 too slow
200-->ok

install nvidia tested
100-->οκ
200-->οκ
enable fractional scale-->turn to 100 itself
150-->black
125-->200
125(200) change back to 100 first
175-->black
200-->ok
on 200, close fractional scale-->instead of return to 100 itself it doubles the area of the desktop (bigger than my real monitor area, so I have to scroll to see the rest of the desktop)
100-->100 with the same large desktop area issue
deactivate fractional scale-->issue remain
logout,logon--> 100 & ok