Apple releases Safari Technology Preview browser for developers to test latest web technologies

By , Mar 30, 2016

Safari TEchnology Preview teaser 001

Wednesday, Apple announced immediate availability of a brand new browser created specifically for web developers. Safari Technology Preview, as it’s called, resembles an ordinary Safari browser with a distinctively purple app icon in the dock. With Safari Technology Preview, web developers can get their hands on improvements to WebKit and other web technologies and optimize their web code before these technologies trickle down in future releases of iOS and OS X.

“Get a sneak peek at upcoming Safari web technologies in OS X and iOS, and easily experiment with these technologies in your websites and extensions,” writes Apple.

Getting a sneak peek at upcoming web technologies

“Safari Technology Preview gives you an early look at upcoming web technologies in OS X and iOS including the latest layout technologies, visual effects, and developer tools so you can provide input on how they are implemented and deliver a best-in-class user experience on all Apple devices,” reads a notice on Apple’s website.

In addition to previewing the latest advances in HTML, JavaScript and CSS, the browser includes the most recent version of the WebKit rendering engine and the latest version of the Web Inspector and Responsive Design Mode tools for modifying, debugging and optimizing websites.

Safari TEchnology Preview app icon full size

Developers can provide feedback using the built-in Bug Reporter tool and run the new browser side-by-side with the consumer version of Safari and more.

Safari Technology Preview uses iCloud so all your latest favorites, bookmarks and Reading List are available to you. It updates easily via the Mac App Store’s Updates tab every few weeks with the most recent additions and improvements to WebKit.

Safari Technology Preview release notes

The inaugural release of Safari Technology Preview comes with the following list of features listed in the official release notes that accompany the download:

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

You can download Safari Technology Preview at

To stay in the loop on the latest developments in HTML, JavaScript and CSS, check out the official WebKit blog.

Source: Apple

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  • Should have came up with a shorter name.

    • Jackson Grong

      They didn’t.

    • Gregg

      Shld hv cm p wth shrtr nm.


  • Jovani Hernandez

    Thers always has to be someone criticize if it’s not “low ram” to looks the same or even the name is too long someone always has a critic

  • Mr_Coldharbour

    Started using it briefly today. Haven’t noticed that much of a difference between it and the latest Safari on El Capitane 10.11.4 but I’m sure it’s more back-end improvements and enhances. Though one major thing to point out is that the 1Password Safari extension doesn’t work for obvious reasons (it’s a beta app that was just released several hours ago), it will install but won’t fill out username / password forms. Some other extensions are semi-broken (I guess) such as Incognito for Safari. Otherwise, I’d like to see how fast HTML5 videos load compared to the current Safari.