Add optdepends: xdg-desktop-portal-gtk
It's list in: https://community.kde.org/Distributions/Packaging_Recommendations
The description is from the above link, but it is not complete, so you might want to change it:
- It also syncs cursor size/theme in addition to fonts.
- Some native GTK apps (e.g. Firefox) or other 3rd-party apps (e.g. Kitty) also get cursor size config from it.