Maven Attached Artifact (classifier) Deployed but Inaccessible

I have a maven module which is configured with a feature packaging (an Apache Karaf feature). This project has no primary artifact to deploy but an attached feature.xml file. When I try to deploy the project to Github package the upload seems to work:

Uploaded to github:

But then, the above file does not show up in the Github Packages UI and other projects cannot depend on it (404). Note the pom is well deployed as the other sibling jar modules.

Any idea?
Thanks for help.