Davide

API to register a command to be displayed in the Userscripts pop-up menu. Reference: [Greasemonkey](https://wiki.greasespot.net/GM.registerMenuCommand), [Violentmonkey](https://violentmonkey.github.io/api/gm/#gm_registermenucommand), and [Tampermonkey](https://www.tampermonkey.net/documentation.php#GM_registerMenuCommand).