+Valid values are:
+
+=over 8
+
+=item * match=domain
+- Only include inboxes with URLs which belong to the domain of
+the HTTP request. This is compatible with virtual hosting where
+several domains come from the same host.
+
+=item * all
+- All inboxes are present in C<manifest.js.gz>, regardless of domain.
+Only use this if you're serving HTTP requests in a domain-agnostic manner.
+
+=item * 404
+- C<manifest.js.gz> will only contain an empty JSON array.
+This does NOT affect C<$INBOX_URL/manifest.js.gz>, which will
+always contain all git repos used by the inbox at C<$INBOX_URL>