https://www.nazwa.pl/blog/wp-content/themes/byblog/js/keyboard-image-navigation.js?ver=1.0

1/**
2 * Byblog keyboard support for image navigation.
3 */
4
5function notify() {
6  alert( "clicked" );
7}
8
9( function( $ ) {
10	$( document ).on( 'keydown.byblog', function( e ) {
11		var url = false;
12
13		// Left arrow key code.
14		if ( 37 === e.which ) {
15			url = $( '.nav-previous a' ).attr( 'href' );
16
17		// Right arrow key code.
18		} else if ( 39 === e.which ) {
19			url = $( '.nav-next a' ).attr( 'href' );
20
21		// Other key code.
22		} else {
23			return;
24		}
25
26		if ( url && ! $( 'textarea, input' ).is( ':focus' ) ) {
27			window.location = url;
28		}
29	} );
30} )( jQuery );