HTML Import webcomponents polyfill not working in firefox

Question

I am trying webcomponents in a sample app. Since some of the specs are not included in some browsers, i tried using polyfill for those. In Mozilla firefox, i tried by enabling the key dom.webcomponents.enabled and adding some polyfills (that are not in browser). I have used HTML Import polyfill from webcomponents.js polyfill.

Still HTMLImport is not working in firefox, internet explorer (even with polyfill). (https://github.com/webcomponents/webcomponentsjs)

I also tried customElements v1 polyfill, not working in internet explorer and firefox. (https://github.com/webcomponents/custom-elements)

Has anybody succeeded in including HTMLimports polyfill with customElements V1 polyfill?

Supersharp Supersharp · Accepted Answer · 2017-01-19T10:45:14

To use, in Firefox, Custom Elements v1 with HTML Imports:

Do not activate Firefox flags as the implementation is outdated.
Install webcomponentsjs (with bower for example), and include in your main file only htmlimports.min.js file.
Install custom-elements (from your link) and include in your main file custom-elements.min.js.

You main page should look like this:

<head>
   <script src="htmlimports.min.js"></script>
   <script src="custom-elements.min.js"></script>
   <link rel="import" href="your-components.html">
</head>
<body>
    <your-component></your-component>

NB: for step 3, you can also use document-register-element.

You cannot use Custom Elements v1 class syntax with Internet Explorer directly because class is not implemented. You'll need first to transform the source code with a transpiler like Babel.

Alternately, use a modern version (Edge), or use the prototype syntax.

HTML Import webcomponents polyfill not working in firefox

1 Answers