lib/PublicInbox/WWW.pm | 5 ++---
 t/psgi_search.t        | 4 ++++

diff --git a/lib/PublicInbox/WWW.pm b/lib/PublicInbox/WWW.pm
index 8f4bfd0f36bf293b9df1b89a2d74229b195e4bf0..841a7e8590c493e6523b355394a66617054e9546 100644
--- a/lib/PublicInbox/WWW.pm
+++ b/lib/PublicInbox/WWW.pm
@@ -50,10 +50,9 @@ 	# we don't care about multi-value
 	%{$ctx->{qp}} = map {
 		utf8::decode($_);
 		tr/+/ /;
-		my ($k, $v) = split('=', $_, 2);
-		$v = uri_unescape($v // '');
+		my ($k, $v) = split(/=/, $_, 2);
 		# none of the keys we care about will need escaping
-		$k => $v;
+		($k // '', uri_unescape($v // ''))
 	} split(/[&;]+/, $env->{QUERY_STRING});
 
 	my $path_info = path_info_raw($env);
diff --git a/t/psgi_search.t b/t/psgi_search.t
index d59e439b124777a53e7f9d07d56348a0d096f2e3..5bdd66edf2bee703e68fd5646d34cc4821dd6d54 100644
--- a/t/psgi_search.t
+++ b/t/psgi_search.t
@@ -88,6 +88,10 @@ 	$res = $cb->(GET('/test/?q=s:test&l=5e'));
 	is($res->code, 200, 'successful search result');
 	is_deeply([], $warn, 'no warnings from non-numeric comparison');
 
+	$res = $cb->(GET('/test/?&q=s:test'));
+	is($res->code, 200, 'successful search result');
+	is_deeply([], $warn, 'no warnings from black parameter');
+
 	$res = $cb->(POST('/test/?q=s:bogus&x=m'));
 	is($res->code, 404, 'failed search result gives 404');
 	is_deeply([], $warn, 'no warnings');