--- a/mercurial/statichttprepo.py	Wed Apr 17 23:10:29 2019 -0700
+++ b/mercurial/statichttprepo.py	Sat Apr 06 17:46:19 2019 +0200
@@ -155,6 +155,7 @@
 
         self.names = namespaces.namespaces()
         self.filtername = None
+        self._extrafilterid = None
 
         try:
             requirements = set(self.vfs.read(b'requires').splitlines())