diff --git a/demo/package.json b/demo/package.json
index 8ded66f0..6403c198 100644
--- a/demo/package.json
+++ b/demo/package.json
@@ -5,10 +5,10 @@
     "homepage": "https://plyr.io",
     "author": "Sam Potts <sam@potts.es>",
     "dependencies": {
-        "core-js": "^3.1.4",
+        "core-js": "^3.6.4",
         "custom-event-polyfill": "^1.0.7",
         "raven-js": "^3.27.2",
         "shr-buttons": "2.0.3",
-        "url-polyfill": "^1.1.5"
+        "url-polyfill": "^1.1.8"
     }
 }