Run analysis Install PHPStan composer require --dev phpstan/phpstan Download : phpstan_mdl77341.neon and put the file into Moodle's root folder. Run the analysis: php -dmemory_limit=1G vendor/bin/phpstan analyse --configuration phpstan_mdl77341.neon -vvv | tee result.txt Search for "Access to an undefined property". grep -i "Access to an undefined property" result.txt Verify that you will get the below result: 328    Access to an undefined property mnet_peer::$public_key_ref.                           329    Access to an undefined property mnet_peer::$public_key_ref. Ignore those warnings because the $public_key_ref is in the deprecated function.