Ticket #45361: 45361.2.diff

src/wp-includes/nav-menu.php

@@ -92 +92 @@
 
         add_theme_support( 'menus' );
 
+        foreach ( $locations as $key => $value ) {
+                if ( is_int( $key ) ) {
+                        /* translators: %s: menu location value */
+                        $message = sprintf( __( 'Strings should always be used for menu location slugs.' ), $value );
+                        _doing_it_wrong( __FUNCTION__, $message, '5.2' );
+                        break;
+                }
+        }
+
         $_wp_registered_nav_menus = array_merge( (array) $_wp_registered_nav_menus, $locations );
 }