Apple releases Safari Technology Preview for developers

Apple has launched its new Safari Technology Preview browser for developers, giving them the chance to test drive "incoming web technologies" like visual effects and new layouts before they're released for everyone. Safari Technology Preview is available to download now (it requires the latest versions of El Capitan on desktop), and comes with some advantages over the WebKit Nightly, including support for iCloud, updates every two weeks in the App Store, and being validated/signed by Apple.

Among the things developers will get access to are early looks at changes in WebKit, HTML, CSS, and JavaScript, the newest versions of Responsive Design Mode and Web Inspector, and access to Bug Reporter for alerting Apple about any issue that encountered (it can be used to submit requests, as well).

You'll need to be running OS X 10.11.4 or later if you're downloading on a Mac; anyone can download it here. Check out the Release Notes below:

Release 1

This release of Safari Technology Preview contains the most recent additions and improvements to WebKit and the latest advances in Safari web technologies.

Browser Differences

Safari Technology Preview can be run side-by-side with Safari and set as the default browser

Separate local data stores are used for history, bookmarks, cookies, and cache

Browsing history and bookmarks are synced over iCloud when iCloud sync is enabled

The Develop menu is enabled by default

Receives regular updates through the Updates tab of the Mac App Store

Bug reports made on should specify Safari Technology Preview

JavaScript Improvements

ECMAScript 6 support including lexical scoping, iterators, generators, arrow functions, default parameter values and many new built-in APIs

Better standards compliant IndexedDB support with more stability

Included the B3 JavaScript JIT compiler with low-latency, high-throughput that boosts performance

Added the ability to use `document.execCommand('copy')` and `document.execCommand('cut')` in response to a user gesture to copy and cut text programmatically

HTML Enhancements

The latest implementation of the Shadow DOM specification

Added support for Content Security Policy Level 2

Web Inspector Changes

Added memory summary and JavaScript allocations timelines

Added a fast JavaScript sampling profiler

Improved JavaScript profiling timeline view

Behavior Changes

Included many web compatibility fixes and bug fixes