Copy field value to clipboard

copy-field.js

			let copyBtn = document.getElementById( 'copyBtn' ),
				copyField = document.getElementById( 'fieldID' );

			copyBtn.addEventListener( 'click', function( e ) {
				e.preventDefault();

				copyField.focus();
				copyField.select();

				document.execCommand( 'copy' );

				alert( 'Field copied!' );
			});