Symfony plugin - Twig is not recognizing local Controllers so they are not included in suggestions

I'm using IntelliJ IDEA with Symfony plugin installed including PHP, Twig, PHP Annotations.

Based on documentation: https://www.jetbrains.com/help/phpstorm/symfony-twig.html#twig-variables I was trying to map passed variables from Controller to Template so they will be recognized by Twig template. However when I try to annotate my controller, it's not recognized in IDEA as it is somehow missing dependency for App\Controller package:

It's only suggesting bundle classes:

Therefore I cannot map variables passed by controller to template.

I am testing it with symfony official demo app: https://github.com/symfony/demo

Any suggestion why this is happening or what configuration am I possibly missing? Thank you in advance.