Ticket #42230: 42230.diff

src/wp-includes/capabilities.php

@@ -432 +432 @@
                 break;
         case 'install_languages':
         case 'update_languages':
+                if ( ! function_exists( 'request_filesystem_credentials' ) ) {
+                        require_once( ABSPATH . 'wp-admin/includes/file.php' );
+                }
+
                 if ( ! function_exists( 'wp_can_install_language_pack' ) ) {
                         require_once( ABSPATH . 'wp-admin/includes/translation-install.php' );
                 }