PHP 8.1 throws this: ``` ErrorException: Deprecated: rtrim(): Passing null to parameter #1 ($string) of type string is deprecated #8 /wp-content/plugins/wp-api-swaggerui/wp-api-swaggerui.php(120): WP_API_SwaggerUI::getBasePath #7 /wp-content/plugins/wp-api-swaggerui/wp-api-swaggerui.php(92): WP_API_SwaggerUI::swagger #6 /wordpress/wp-includes/class-wp-hook.php(324): WP_Hook::apply_filters #5 /wordpress/wp-includes/class-wp-hook.php(348): WP_Hook::do_action #4 /wordpress/wp-includes/plugin.php(565): do_action_ref_array #3 /wordpress/wp-includes/class-wp.php(835): WP::main #2 /wordpress/wp-includes/functions.php(1342): wp #1 /wordpress/wp-blog-header.php(16): require #0 /index.php(23): null ```