diff --git a/tests/41end-to-end-keys/07-backup.pl b/tests/41end-to-end-keys/07-backup.pl
index 904301308..ad2ec60e3 100644
--- a/tests/41end-to-end-keys/07-backup.pl
+++ b/tests/41end-to-end-keys/07-backup.pl
@@ -1,3 +1,5 @@
+use Future::Utils qw( repeat );
+
 my $fixture = local_user_fixture();
 
 test "Can create backup version",
@@ -347,6 +349,18 @@
       });
    };
 
+# regression test for https://github.com/matrix-org/synapse/issues/4169
+test "Can create more than 10 backup versions",
+   requires => [ $fixture ],
+
+   do => sub {
+      my ( $user ) = @_;
+
+      repeat( sub {
+         matrix_create_key_backup( $user );
+      }, foreach => [ 0 .. 10 ], while => sub { $_[0] -> is_done });
+   };
+
 
 =head2 matrix_create_key_backup