Initial commit. State 04.2021.

wp-content/themes/twentyfifteen/js/skip-link-focus-fix.js

@@ -0,0 +1,26 @@
+/**
+ * Makes "skip to content" link work correctly in IE9, Chrome, and Opera
+ * for better accessibility.
+ *
+ * @link http://www.nczonline.net/blog/2013/01/15/fixing-skip-to-content-links/
+ */
+
+( function() {
+	var ua = navigator.userAgent.toLowerCase();
+
+	if ( ( ua.indexOf( 'webkit' ) > -1 || ua.indexOf( 'opera' ) > -1 || ua.indexOf( 'msie' ) > -1 ) &&
+		document.getElementById && window.addEventListener ) {
+
+		window.addEventListener( 'hashchange', function() {
+			var element = document.getElementById( location.hash.substring( 1 ) );
+
+			if ( element ) {
+				if ( ! /^(?:a|select|input|button|textarea)$/i.test( element.nodeName ) ) {
+					element.tabIndex = -1;
+				}
+
+				element.focus();
+			}
+		}, false );
+	}
+} )();