contentid: ignore duplicate References: headers

OverIdx::parse_references already skips duplicate
References (which we use in SearchThread for rendering).
So there's no reason for our content deduplication logic
to care if a Message-Id in the Reference header is mentioned
twice.

1 files changed, 1 insertions, 2 deletions

diff --git a/lib/PublicInbox/OverIdx.pm b/lib/PublicInbox/OverIdx.pm
index 189bd21d..5f1007aa 100644
--- a/lib/PublicInbox/OverIdx.pm
+++ b/lib/PublicInbox/OverIdx.pm
@@ -230,8 +230,7 @@ sub parse_references ($$$) {
                         warn "References: <$ref> too long, ignoring\n";
                         next;
                 }
-                next if $seen{$ref}++;
-                push @keep, $ref;
+                push(@keep, $ref) unless $seen{$ref}++;
         }
         $smsg->{references} = '<'.join('> <', @keep).'>' if @keep;
         \@keep;