--- a/hgext/notify.py	Fri Feb 18 12:55:39 2022 +0100
+++ b/hgext/notify.py	Fri Feb 18 14:27:43 2022 +0100
@@ -435,7 +435,10 @@
             if spec is None:
                 subs.add(sub)
                 continue
-            revs = self.repo.revs(b'%r and %d:', spec, ctx.rev())
+            try:
+                revs = self.repo.revs(b'%r and %d:', spec, ctx.rev())
+            except error.RepoLookupError:
+                continue
             if len(revs):
                 subs.add(sub)
                 continue