diff -r 3d4e9c994f10 -r a86126ab1dd4 wp/wp-admin/user/admin.php
--- a/wp/wp-admin/user/admin.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-admin/user/admin.php	Tue Dec 15 13:49:49 2020 +0100
@@ -9,14 +9,15 @@
 
 define( 'WP_USER_ADMIN', true );
 
-require_once( dirname( dirname( __FILE__ ) ) . '/admin.php' );
+require_once dirname( __DIR__ ) . '/admin.php';
 
 if ( ! is_multisite() ) {
 	wp_redirect( admin_url() );
 	exit;
 }
 
-$redirect_user_admin_request = ( ( $current_blog->domain != $current_site->domain ) || ( $current_blog->path != $current_site->path ) );
+$redirect_user_admin_request = ( 0 !== strcasecmp( $current_blog->domain, $current_site->domain ) || 0 !== strcasecmp( $current_blog->path, $current_site->path ) );
+
 /**
  * Filters whether to redirect the request to the User Admin in Multisite.
  *
@@ -25,8 +26,10 @@
  * @param bool $redirect_user_admin_request Whether the request should be redirected.
  */
 $redirect_user_admin_request = apply_filters( 'redirect_user_admin_request', $redirect_user_admin_request );
+
 if ( $redirect_user_admin_request ) {
 	wp_redirect( user_admin_url() );
 	exit;
 }
+
 unset( $redirect_user_admin_request );