lib/PublicInbox/View.pm | 6 +++++-

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index e7ca73dc0660aa79054cf5b1acc38e6a78cff249..6fbc366027d0c2d1eda266de34ca95c5d8ba4a2d 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -477,7 +477,11 @@ }
 
 sub anchor_for {
 	my ($msgid) = @_;
-	'm' . mid_compressed(mid_clean($msgid), 1);
+	my $id = $msgid;
+	if ($id !~ /\A[a-f0-9]{40}\z/) {
+		$id = mid_compressed(mid_clean($id), 1);
+	}
+	'm' . $id;
 }
 
 sub simple_dump {