--- a/mercurial/utils/urlutil.py	Fri Oct 15 04:25:58 2021 +0200
+++ b/mercurial/utils/urlutil.py	Fri Oct 15 04:41:24 2021 +0200
@@ -769,6 +769,7 @@
 SUPPORTED_BOOKMARKS_MODES = {
     b'default',
     b'mirror',
+    b'ignore',
 }