Add an optional lookup at | fallback to https://repo.maven.apache.org/maven2/

[michael-simons]

Given a query that contains at least groupId, artifactId and version returns no results from an index based search, consider adding a lookup or a fallback to the actual repository https://repo.maven.apache.org/maven2/.

If the artefact is there, it is already usable in (most) build systems and the lookup would be handy for not having to use the browser .