dart2js compiled Polymer Dart application is not running in IE 11

Question

I am unable to get a dart2js compiled polymer dart project to even load in IE 11. I am a bit confused since it runs in Chrome and Firefox perfectly fine. Here are my steps:

• Used stagehand to create a new web-polymer application.
• Without changing any dependencies, I ran pub get.
• Ran the application in Dartium using Webstorm's Open in Browser -> Dartium and verified the string reversing sample loaded.
• Ran pub build to compile my project into JavaScript.
• Navigated to my build\\web directory, and started up a simple HTTP server (python -m SimpleHTTPServer or node's http-server)
• Opened the IP address and port listed in Chrome and Firefox, application worked as expected
• Opened the IP address and port listed in IE 11 and got a blank page.

I did open up the developer tools in IE 11 and noticed an error being thrown from my index.bootstrap.initialize.dart.js file with the text "Unsupported operation: extendsTag does not match base native class"

Again I did not change anything, I was just curious to see the compiled application run. Is there something I am missing or forgot to do to get this to run in IE 11?

Answer 1

Seems you run into this issue https://github.com/dart-lang/polymer-dart/issues/682

It looks like this does work if you use the full polyfill (webcomponents.js not webcomponents-lite.js).

Looks like this is caused by the template element not existing on IE. The full polyfill adds it which is why that works, where the lite version doesn't do a full polyfill.