public-inbox.cgi | 21 +++++++++++++++++++++
 t/cgi.t          |  8 ++++++++

diff --git a/public-inbox.cgi b/public-inbox.cgi
index 1765cf4549bc51b334ee5061e2176df0a3038040..17eb5b7beb4e0626c7bf6e135f5587cbce0d48a5 100755
--- a/public-inbox.cgi
+++ b/public-inbox.cgi
@@ -46,6 +46,12 @@
 # private functions below
 
 sub main {
+	# some servers (Ruby webrick) include scheme://host[:port] here,
+	# which confuses CGI.pm when generating self_url.
+	# RFC 3875 does not mention REQUEST_URI at all,
+	# so nuke it since CGI.pm functions without it.
+	delete $ENV{REQUEST_URI};
+
 	my $cgi = CGI->new;
 	my %ctx;
 	if ($cgi->request_method !~ /\AGET|HEAD\z/) {
@@ -77,6 +83,8 @@ 		invalid_list_mid(\%ctx, $1, $2) || get_full_html(\%ctx, $cgi);
 	} elsif ($path_info =~ m!$LISTNAME_RE/f/(\S+)\z!o) {
 		redirect_mid_html($cgi, $1, $2);
 
+	} elsif ($path_info =~ m!$LISTNAME_RE\z!o) {
+		invalid_list(\%ctx, $1) || redirect_list_index(\%ctx, $cgi);
 	} else {
 		r404();
 	}
@@ -180,6 +188,19 @@ 	require PublicInbox::View;
 	require Email::MIME;
 	[ "200 OK", {'Content-Type' => 'text/html'},
 		PublicInbox::View->as_html(Email::MIME->new($$x))];
+}
+
+sub redirect_list_index {
+	my ($ctx, $cgi) = @_;
+	do_redirect($cgi->self_url . "/");
+}
+
+sub do_redirect {
+	my ($url) = @_;
+	[ '301 Moved Permanently',
+	  { Location => $url, 'Content-Type' => 'text/plain' },
+	  "Redirecting to $url\n"
+	]
 }
 
 # only used for CGI and static file generation modes
diff --git a/t/cgi.t b/t/cgi.t
index ae7cc730e7203ea1c1c5991233d52a7dff7597ea..c8755541211ffd3757480ba8b519a851a17e0831 100644
--- a/t/cgi.t
+++ b/t/cgi.t
@@ -181,6 +181,14 @@ 	like($res->{body}, qr/slashy%2Fasdf%40example\.com/,
 		"slashy URL generated correctly");
 }
 
+# redirect list-name-only URLs
+{
+	local $ENV{HOME} = $home;
+	my $res = cgi_run("/test");
+	like($res->{head}, qr/Status: 301 Moved/, "redirected status");
+	like($res->{head}, qr!/test/!, "redirected with slash");
+}
+
 done_testing();
 
 sub run_with_env {