#include "typing_follow_effect.h" extern struct zmk_led_hsb zmk_rgb_underglow_current_color; struct zmk_led_hsb original = zmk_rgb_underglow_current_color; ...

I don't see typing_extensions in the pyproject.toml, at first I thought maybe it was missing. However I see in the typer project that they have removed the need to import typing_extensions in ver 0.15 ...