help: do not abort topicmatch() because of unimportable extensions This is alternative workaround to D1198, originally spotted by the earlier version of the releasenotes extension.

{
    "conduit_uri": "https://phab.mercurial-scm.org/api",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}