The Windows 10 Anniversary Update has started rolling out to end users, giving web developers a chance to use some of the new features in the newest version of Edge, including the latest HTML rendering engine, Windows Hello, and browser extensions.
EdgeHTML 14, the newest version of Microsoft's HTML rendering engine, is now in the stable channel, and includes a number of updates for both HTML and JavaScript. HTML improvements include the <output> and <data> elements as well as the <input type=color>. WOFF 2.0 fonts are supported, which Microsoft says helps reduce the size of font files by 30%.
For JavaScript, the new release supports async/await, default parameters, and Object.values and Object.entries. The ES2016 exponentation operator (**) is also available.
An important new feature is the Fetch API. When fully implemented by browsers, fetch stands to eliminate the need for the ubiquitous XMLHttpRequest (XHR). Now that Edge has shipped it, Safari becomes the only desktop browser lacking the feature. Until then, developers can use the fetch polyfill to support all browsers.
Edge, the browser itself, now supports extensions. A number of extensions, such as Amazon Assistant, LastPass, Evernote Web Clipper, and AdBlock Plus can be installed from the Store. Microsoft has been working with a small group of external developers to get these extensions up. They have not yet published guidance on how developers can write their own extensions and get them published in the store. Currently, Microsoft's extensions documentation asks developers to stay tuned:
We’re currently building and validating our extension platform and documentation with the help of a small number of extension authors. Please stay tuned for future updates!
So far, many extension API features are available, but more are under consideration. Enterprise developers will be able to offer up custom extensions meant solely for internal use.
Also available to web developers is Windows Hello. By enabling Windows Hello, users can authenticate to the web app using the machine's built-in security features.
For those that don't have a Windows 10 PC available, Edge 14 VMs are available to test out the new features.
For the full list of changes since the last major Windows 10 release, check out the Edge Release Notes. The version shipped with the anniversary update is build 14393.