Technically Elementor is not required. However, without Elementor being activated this plugin (Toolbar Extras) doesn’t make much sense. The plugin supports deactivation of Elementor, though (for development, testing, whatever). When you do that (maybe for testing something) nothing strange will happen; I’ve included a fallback. Toolbar Extras acts smart 🙂
I totally recommend Elementor – so, with it active, this plugin here will make the perfect sense!