fix: prevent white screen and errors on Widget Screen (#1390)

newspack-theme/functions.php

@@ -427,6 +427,13 @@ function newspack_enqueue_scripts() {
 	$languages_path = get_parent_theme_file_path( '/languages' );
 	$theme_version  = wp_get_theme()->get( 'Version' );
 	$post_type      = get_post_type();
+	$current_screen = get_current_screen();
+
+	// Add check to see if currently on the widgets screen; none of these files are needed there, but are loaded as of WP 5.8.
+	// See: https://github.com/WordPress/gutenberg/issues/28538.
+	if ( 'widgets' === $current_screen->id ) {
+		return;
+	}
 
 	// Featured Image options.
 	wp_register_script(

newspack-theme/js/src/amp-fallback.js

@@ -40,14 +40,10 @@
 
 	// Menu toggle variables.
 	const mobileToggle = document.getElementsByClassName( 'mobile-menu-toggle' ),
-		body = document.getElementsByTagName( 'body' )[ 0 ],
+		body = document.body,
 		mobileSidebar = document.getElementById( 'mobile-sidebar-fallback' ),
-		mobileOpenButton = headerContain.getElementsByClassName( 'mobile-menu-toggle' )[ 0 ],
-		mobileCloseButton = mobileSidebar.getElementsByClassName( 'mobile-menu-toggle' )[ 0 ],
 		desktopToggle = document.getElementsByClassName( 'desktop-menu-toggle' ),
 		desktopSidebar = document.getElementById( 'desktop-sidebar-fallback' ),
-		desktopOpenButton = headerContain.getElementsByClassName( 'desktop-menu-toggle' )[ 0 ],
-		desktopCloseButton = desktopSidebar.getElementsByClassName( 'desktop-menu-toggle' )[ 0 ],
 		subpageToggle = document.getElementsByClassName( 'subpage-toggle' );
 
 	/**
@@ -96,6 +92,9 @@
 
 	// Mobile menu fallback.
 	for ( let i = 0; i < mobileToggle.length; i++ ) {
+		const mobileOpenButton = headerContain.querySelector( '.mobile-menu-toggle' ),
+			mobileCloseButton = mobileSidebar.querySelector( '.mobile-menu-toggle' );
+
 		mobileToggle[ i ].addEventListener(
 			'click',
 			function() {
@@ -111,6 +110,9 @@
 
 	// Desktop menu (AKA slide-out sidebar) fallback.
 	for ( let i = 0; i < desktopToggle.length; i++ ) {
+		const desktopOpenButton = headerContain.querySelector( '.desktop-menu-toggle' ),
+			desktopCloseButton = desktopSidebar.querySelector( '.desktop-menu-toggle' );
+
 		desktopToggle[ i ].addEventListener(
 			'click',
 			function() {
@@ -127,8 +129,8 @@
 	// 'Subpage' menu fallback.
 	if ( 0 < subpageToggle.length ) {
 		const subpageSidebar = document.getElementById( 'subpage-sidebar-fallback' ),
-			subpageOpenButton = headerContain.getElementsByClassName( 'subpage-toggle' )[ 0 ],
-			subpageCloseButton = subpageSidebar.getElementsByClassName( 'subpage-toggle' )[ 0 ];
+			subpageOpenButton = headerContain.querySelector( '.subpage-toggle' ),
+			subpageCloseButton = subpageSidebar.querySelector( '.subpage-toggle' );
 
 		for ( let i = 0; i < subpageToggle.length; i++ ) {
 			subpageToggle[ i ].addEventListener(