diff -r ef0e3cc684b3 -r 70b71421fd33 mercurial/localrepo.py
--- a/mercurial/localrepo.py	Mon May 21 17:28:35 2018 +0200
+++ b/mercurial/localrepo.py	Thu Apr 04 13:58:49 2019 +0200
@@ -2107,6 +2107,7 @@
             # accessing the 'ser ved' branchmap should refresh all the others,
             self.ui.debug('updating the branch cache\n')
             self.filtered('served').branchmap()
+            self.filtered('served.hidden').branchmap()
 
         if full:
             unfi = self.unfiltered()