Tested Geany Editor on Windows the other day, it uses GTK, great editor but horribly slow on Windows, just scrolling a small file (less than 100 lines) was sluggish.

MSYS2. And copy over prebuilt dependencies. And while we say C++, I suggest always to use Meson as build tool. Which allows you to use WrapDB (built in dependency-manager) aside from available native libraries and own local sources.

MSYS2: https://www.msys2.org

Meson: https://mesonbuild.com

The problem about Windows is, that Microsoft adds new APIs repeatingly and doesn’t care much about the previous ones. While on Linux we’ve Gtk1, Gtk2, Gtk3 and Gtk4.

And while people complain about deprecations and changes they actually mean „API changes require work to use the new major. But these people keep maintaining it. And provide upgrade paths to enhanced versions? I’m in!“.

HiDPI, Wayland, new Widgets, new renderers and a scene-graph.

PS: If you need to keep it small and simple and address professional (power) users I suggest a TUI with the venerable ncurses. Or notcurses.

Notcurses: https://github.com/dankamongmen/notcurses.

Demo of Ncurses (For the lulz): https://www.youtube.com/watch?v=dcjkezf1ARY