Hey Maurice!

 MK> GRUB_GFXMODE=auto

Change the above to "GRUB_GFXMODE=3840x2160x32,2560x1440x32,1920x1080x32,1280x800x32,1024x768x32,800x600x32,auto".  Now /etc/default/grub looks like;

-={ /etc/default/grub starts }=-
GRUB_DISABLE_LINUX_UUID=true
GRUB_DISABLE_LINUX_PARTUUID=false
GRUB_GFXMODE=3840x2160x32,2560x1440x32,1920x1080x32,1280x800x32,1024x768x32,800x600x32,auto
GRUB_GFXPAYLOAD_LINUX=keep
GRUB_TERMINAL_OUTPUT="gfxterm"
GRUB_FONT=/boot/efi/EFI/ZNVER2_NVME/test.ttf
-={ /etc/default/grub ends   }=-

I threw in two 4:3 resolutions at the end for no additional cost just for you.  As shown 3840x2160 (aka 4k) is the default but will successfully launch a different resolution as it moves to the right until it hits a compatible one.

 MK> console-font such as latarcyrheb-sun32 which is what I am deploying.

It looks awesome on 4k, especially a fullscreen TERM=linux display such as the one I am currently looking at.

The 16 boot penguins are pure bonus.  It was worth the effort.

Life is good,
Maurice

... Bliše sceal bealoleas heorte.
    Happy is the guiltless heart.
--- GNU bash, version 5.1.16(1)-release (x86_64-lilmikii-linux-gnu)