diff --git a/vendor/fbtransform/transforms/xjs.js b/vendor/fbtransform/transforms/xjs.js
index 27a8020f5ce5e..95881f16ea45a 100644
--- a/vendor/fbtransform/transforms/xjs.js
+++ b/vendor/fbtransform/transforms/xjs.js
@@ -106,6 +106,7 @@ var knownTags = {
   p: true,
   param: true,
   path: true,
+  polygon: true,
   polyline: true,
   pre: true,
   progress: true,