4K monitor. Everything is very small

I changed the monitor to a high resolution 3840 x 2160. Everything becomes very tiny, including panels. Is it possible to change everything to normal size without great work? In config of the panel, the pixels were used, and recalculate everything is rather difficult.

Is anybody who can help me? I’m sure that this is an usual problem now because the 4k monitors now is everywhere.

Same here. I am using a 1920x1080 monitor and things are also abysmally small. I’ve looked everywhere in FVWM documentations and can’t find a way to set a global UI scale factor in the config file.

I found solutions for myself. First way. My fvwm is over Linux Mint Mate 20. I enter the computer under Linux Mint and configured themes and fonts. It is very simple in Mint. Then I enter to computer under fvwm and start in terminal mate-appearance-properties. The window of parameters appears, closed it and vu a la, I have all fonts and themes as in Mint. Then it is easy to put in fvwm config this option. The second way, which I use. I made file ~.config/gtk-3.0/settings.ini and put in it
gtk-theme-name = Mint-X
gtk-icon-theme-name = Adwaita
gtk-cursor-theme-name = whiteglass
gtk-cursor-theme-size = 20
gtk-font-name = Sans 22
gtk-overlay-scrolling = 0
gtk-dialogs-use-header = 0
It works well. For qt applications enlarging fonts is vie qt5ct. Some applications do not use this configuration. For example, megasync I start with sh file where I set parameters for fonts. Another problem with the size of windows in some applications. Double commander, for instance, parameters window has right fonts but the size for text is not enlarged.
I did not find a solution in a single step to enlarge everything and recalculated everything in the config for the panel. I try to make unification the panel in a way that everything is calculated by using the resolution of the screen. I’m sure it is possible. I tried to use this suggestion https://ricostacruz.com/til/fractional-scaling-on-xorg-linux but it works very strange. Something large, something tiny. If you find solution on single step, please let me know.