Ticket #35155: 35155.patch

src/wp-admin/admin-header.php

@@ -169 +169 @@
         $admin_body_class .= ' network-admin';
 
 $admin_body_class .= ' no-customize-support no-svg';
-
+// Print a CSS class to make PHP errors visible.
+if ( error_get_last() ) {
+        $admin_body_class .= ' php-error';
+}
 ?>
 </head>
 <?php

src/wp-admin/css/admin-menu.css

@@ -13 +13 @@
         z-index: 1; /* positive z-index to avoid elastic scrolling woes in Safari */
 }
 
+.php-error #adminmenuback {
+        position: absolute;
+}
+
+.php-error #adminmenuback,
+.php-error #adminmenuwrap {
+        margin-top: 20px;
+}
+
 #adminmenu {
         clear: left;
         margin: 12px 0;