lib/PublicInbox/Reply.pm |  3 +++
 t/reply.t                | 16 +++++++++++-----

diff --git a/lib/PublicInbox/Reply.pm b/lib/PublicInbox/Reply.pm
index 8226fdc3c755e9cecb7cc66ee2fb4eae1fc23026..2a1066d2b47f89b37f14a6b2784c8c8de26c6cbb 100644
--- a/lib/PublicInbox/Reply.pm
+++ b/lib/PublicInbox/Reply.pm
@@ -74,6 +74,7 @@ 	my @arg;
 	my $obfs = $ibx->{obfuscate};
 	my $subj = $hdr->header('Subject') || '';
 	$subj = "Re: $subj" unless $subj =~ /\bRe:/i;
+	my $subj_raw = $subj;
 	my $mid = $hdr->header_raw('Message-ID');
 	push @arg, '--in-reply-to='.squote_maybe(mid_clean($mid));
 	my $irt = mid_href($mid);
@@ -102,6 +103,8 @@ 			$cc = '&Cc=' . uri_escape_utf8(join(',', @cc));
 			push(@arg, map { "--cc=$_" } @cc);
 		}
 	}
+
+	push @arg, "--subject=".squote_maybe($subj_raw);
 
 	# I'm not sure if address obfuscation and mailto: links can
 	# be made compatible; and address obfuscation is misguided,
diff --git a/t/reply.t b/t/reply.t
index 0b8e1f38f720b6c2e9d631df4c71878d80f2acbf..1e89973e0730c92d346b51f2c66cfda1c4245f32 100644
--- a/t/reply.t
+++ b/t/reply.t
@@ -36,7 +36,8 @@ my $exp = [
     '--in-reply-to=blah@example.com',
     '--to=from@example.com',
     '--cc=cc@example.com',
-    '--cc=to@example.com'
+    '--cc=to@example.com',
+    "--subject='Re: hihi'"
 ];
 
 is_deeply($arg, $exp, 'default reply is to :all');
@@ -44,7 +45,8 @@ $ibx->{replyto} = ':all';
 ($arg, $link) = PublicInbox::Reply::mailto_arg_link($ibx, $hdr);
 is_deeply($arg, $exp, '":all" also works');
 
-$exp = [ '--in-reply-to=blah@example.com', '--to=primary@example.com' ];
+$exp = [ '--in-reply-to=blah@example.com', '--to=primary@example.com',
+	"--subject='Re: hihi'" ];
 $ibx->{replyto} = ':list';
 ($arg, $link) = PublicInbox::Reply::mailto_arg_link($ibx, $hdr);
 is_deeply($arg, $exp, '":list" works for centralized lists');
@@ -53,7 +55,8 @@ $exp = [
 	 '--in-reply-to=blah@example.com',
 	 '--to=primary@example.com',
 	 '--cc=cc@example.com',
-	 '--cc=to@example.com'
+	 '--cc=to@example.com',
+	"--subject='Re: hihi'"
 ];
 $ibx->{replyto} = ':list,Cc,To';
 ($arg, $link) = PublicInbox::Reply::mailto_arg_link($ibx, $hdr);
@@ -61,7 +64,9 @@ is_deeply($arg, $exp, '":list,Cc,To" works for kinda centralized lists');
 
 $ibx->{replyto} = 'new@example.com';
 ($arg, $link) = PublicInbox::Reply::mailto_arg_link($ibx, $hdr);
-$exp = [ '--in-reply-to=blah@example.com', '--to=new@example.com' ];
+$exp = [ '--in-reply-to=blah@example.com', '--to=new@example.com',
+	"--subject='Re: hihi'"
+];
 is_deeply($arg, $exp, 'explicit address works, too');
 
 $ibx->{replyto} = ':all';
@@ -71,7 +76,8 @@ $exp = [
     '--in-reply-to=blah@example.com',
     '--to=from@example$(echo .)com',
     '--cc=cc@example$(echo .)com',
-    '--cc=to@example$(echo .)com'
+    '--cc=to@example$(echo .)com',
+    "--subject='Re: hihi'"
 ];
 is_deeply($arg, $exp, 'address obfuscation works');
 is($link, '', 'no mailto: link given');