The primary branch in the Wikidata Query Builder deployment repo is production, which is automatically deployed via Puppet. But it also has a master branch:
The branch is quite outdated, and seems to be left over from the initial work in the deployment repo (T266703), before we switched the branch (though I don’t understand the “To avoid constant merge conflicts” comment). Puppet has cloned the production branch since the initial setup there. I propose that we delete the branch to avoid confusion. (Note that HEAD still points at master – we should move that to production too.)
See also the comments of T254027, where the master branch of the similar wikidata/query/gui-deploy repository was deleted.
