I know it is possible on Ubuntu 20.04 if not also on 18.04 to scale fractional without steps (see Screenshot of Settings > Devices > Displays) but how do I achieve this on Zorin OS? 100% is too small, 200% is too big.
If the screen resolution is 2K or more the text sizes are too small. If I set "Large Text" under Settings > Universal Access the text size is fine but if it is not large enough I cannot zoom (e. g. in Evolution Mail Client if I write a new message). Obviously I can't increase the text size as such, because it will be too large for the recipient.
Downscaling to less than 2K is not really an option since the fonts look very bad even if I adjust settings of the screen firmware.
I also used gnome-tweaks but it will only change the font size as "Large Text" under Settings > Universal Access does.