[buffyboard](https://gitlab.postmarketos.org/postmarketOS/buffybox/-/tree/master/buffyboard)
is the on-screen framebuffer keyboard provided by postmarketOS's
buffybox project.
enable this with `services.buffybox.enable = true;`: any additional
settings are strictly optional.
once enabled, tab to an unused TTY (e.g. Ctrl+Alt+F2) and use the
mouse/touchpad/touchscreen to use the virtual keyboard. may require
a manual `systemctl start buffybox` if enabled on an already-booted
device.
Co-authored-by: Luflosi <luflosi@luflosi.de>