I already griped at danielbeck, but figured I would file a proper ticket

Right now there are no released versions of "Modern SCM" that would fill in the drop-down in the "Pipeline Libraries 'Add'" section. The fact that this is shown, and is the default source for Pipeline Libraries is confusing.

The ideal fix, IMO, would be to only show "Modern SCM" if t here are implementations loaded into the Jenkins instance which support those extension points.