zmk_mf68/app/tests/keytoggle/behavior_keymap.dtsi

#include <dt-bindings/zmk/keys.h>
#include <behaviors.dtsi>
#include <dt-bindings/zmk/kscan_mock.h>

/ {
	keymap {
		compatible = "zmk,keymap";
		label ="Default keymap";

		default_layer {
			bindings = <
				&kt B &none
				&none &none
			>;
		};
	};
};