The recent feature TopicTrait that allows to filter GitHub repository based on GitHub Topic does not find forked repositories.

The Organization scan does not even find the repositories:

01:29:56 Looking up repositories of organization test-org
01:29:56 Looking up repositories for topics: '[test]'
01:29:56 0 repositories were processed

As workaround, the Name filter (wildcard or regexp) can be used instead.

Looking through the code, this seems to be due to the default behavior of the search API - that is used in the context of the topic filter - that does not list forked repositories by default https://docs.github.com/en/search-github/searching-on-github/searching-for-repositories.

Note: When changes are committed to the fork repo, the webhook event received by Jenkins properly finds the fork and create the repository folder. But the Org scan never finds it and would eventually remove it.