Group search does not return results via UI or REST API

Browsing the UI using the group or releases repo shows the same artifacts but searching using the UI returns no results for the group. Searching using the REST API returns the artifact for the releases repo but not for the group.

Steps to reproduce:

Create a maven releases repo and add an artifact

Create a maven group repo just containing the above releases repo.

Search for artifacts in the releases repo and the artifact is returned

Same search against the group repo returns no results.

Example REST API searches below.

Fails:

curl -u admin:admin123 -v -X GET "http://localhost:8089/service/rest/v1/search?repository=mvngrp&format=maven2&group=webgoat&name=webgoat&version=6.0.1&maven.extension=war" -H "accept: application/json"

Works:

curl -u admin:admin123 -v -X GET "http://localhost:8089/service/rest/v1/search?repository=maven-releases&format=maven2&group=webgoat&name=webgoat&version=6.0.1&maven.extension=war" -H "accept: application/json"