Zeitfresser-Wordpress-Theme/inc/blocks/font-customization/line-height/customizer-line-height.js

jQuery( function( $ ) {

	wp.customize('line_height',function ( value ) {
		value.bind(function ( to ) {
		        document.body.style.setProperty('--line-height', to);
		    }
		);
	} );

} );