I created an extension that was annotated with the variants @OptionalExtension marker with required-plugins="something-not-installed"

When running the plugin in Jenkins without the required plugin I expected my Extension not to be present, but it was present and active (as shown by ExtensionList.lookup

It seems as though the requirement is not checked before creating the extension which is contrary to the documentation.

NB, looked at this quickly with danielbeck and we could not see anything wrong in the plugin I was writing