I have 2/3 monitor setup
nr #1 – 5120×2160 (21:9) AKA "5K"
nr #2 – 1920×1080 (16:9)
nr #3 – 1920×1080 (16:9) – connected and used only occasionally
It`s messy. Default resolution detected by system for #1 is 3440×1440. After switching to the full native resolution of "5K" it looks way better but UI elements and text are uncomfortably small.
When I change scaling for #1, #2 is changing as well :/
Also, I'm glad to see Fractional Scaling build in Gnome Display Settings but it's buggy in my case:
#1 set to 150% scaling – as you can see in this screenshot (although it doesn't reflect the problem 100%) its messed up. On #2 I can go only to half the height of the screen where the top bar is being displayed. Wallpaper is messed up. It's unusable.
Wayland is unavailable for me since I use Nvidia GPU.
I wouldn't like to lower my resolution on #1 as a workaround.
So my question is:
How to set up #1 to 200% while keeping #2 (and #3 at some occasions) at 100%.
Best Answer
I solved this question simply installing gdm3 and choosing this display manager instead of lightdm which was the default installation of ubuntu session on 20.04 release. Now it is possible choose different ad fractional scaling on multiple monitors (eg. native 1920x1080 and 3840x2160 on auxiliary monitor)