Using the https://github.com/wikimedia/mediawiki-oauthclient-php client I see these in the logs
mod_fastcgi.c.487) FastCGI-stderr:PHP Notice: Undefined property: stdClass::$key in /public_html/vendor/mediawiki/oauthclient/src/Client.php on line 181
mod_fastcgi.c.487) FastCGI-stderr:PHP Notice: Undefined property: stdClass::$secret in /public_html/vendor/mediawiki/oauthclient/src/Client.php on line 181
Is this something to be concerned about or is the code just missing the at symbol in front of a $return->key and $return->secret?