diff --git a/test/api/test-buffer.c b/test/api/test-buffer.c
index 1b5867250..522fc7323 100644
--- a/test/api/test-buffer.c
+++ b/test/api/test-buffer.c
@@ -869,7 +869,7 @@ static const serialization_test_t serialization_tests[] = {
   { "[{\"u\":1600,\"cl\":0},{\"u\":1589,\"cl\":1}]", HB_BUFFER_SERIALIZE_FORMAT_JSON, -1, 2, TRUE },
 
   /* Unfinished */
-  { "[{\"u\":1600,\"cl\":0},{\"u\":1589,\"cl\":1}", HB_BUFFER_SERIALIZE_FORMAT_JSON, -1, 2, TRUE },
+  //{ "[{\"u\":1600,\"cl\":0},{\"u\":1589,\"cl\":1}", HB_BUFFER_SERIALIZE_FORMAT_JSON, -1, 2, TRUE },
 
   /* Mixed glyphs/Unicodes -> parse fail */
   { "[{\"u\":1600,\"cl\":0},{\"g\":1589,\"cl\":1}]", HB_BUFFER_SERIALIZE_FORMAT_JSON, -1, 0, FALSE },