diff --git a/package.json b/package.json
index 9a5590a9..0222624b 100644
--- a/package.json
+++ b/package.json
@@ -40,7 +40,7 @@
   },
   "dependencies": {
     "pxt-common-packages": "0.22.7",
-    "pxt-core": "3.12.19"
+    "pxt-core": "3.12.21"
   },
   "scripts": {
     "test": "node node_modules/pxt-core/built/pxt.js travis"