Safari Technology Preview for Mac OS X Released, Aimed at Developers

Mar 30, 2016 - 13 Comments

Safari Technology Preview has a purple icon on Mac

Apple has released a new developer focused version of Safari, called Safari Technology Preview. The new browser is aimed at more advanced Mac users who want to “get a sneak peak at upcoming web technologies in OS X and iOS” and test those experimental technologies on websites, web applications, and with Safari extensions and plug-ins.

The Safari Technology Preview installs as a separate version of the Safari browser, distinct with a purple icon, and runs as an entirely separate application. This makes Safari Technology Preview a lot like Google Chrome Canary, and it means there isn’t any risk in downloading and running the Safari Tech Preview build alongside the regular Safari browser. Users can even choose to have the tech preview set as their default web browser on the Mac if desired, though that is likely only beneficial to web developers and those in related industries.

The first version of Safari TP arrives as a dmg with a simple package installer, and requires OS X 10.11.4 or later to be installed on the Mac.

Safari Technology Preview

Updates to the Safari Tech Preview app will arrive on the Mac via the Mac App Store. Because the app is separate from Safari, there is no additional software necessary to use the build, and there is no enrollment in a beta testing program. You can find both apps side by side in the /Applications/ folder after it has been installed.

Safari Tech Preview on Mac

The first build of Safari Technology Preview includes the following release notes:

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

Preliminary testing of Safari Tech Preview suggest the first build is fast, and quite stable without any obvious problems or major issues, perhaps making it usable as a daily web browser for those who are comfortable with the idea of running what is essentially developer centric software. It remains to be seen if the new Safari Tech Preview is impacted by the same freezing issue that impacts some users with Safari in OS X 10.11.4.

Aside from the purple icon, the Safari Tech Preview browser looks identical to the normal Safari browser:

Safari Tech Preview in Mac OS X

Users can install plugins and extensions in Safari Tech Preview without impacting the normal Safari browser, and vice versa. The regular and Safari Tech Preview app also contain their own caches, cookies, and history.


Related articles:

Posted by: Paul Horowitz in Mac OS, News


» Comments RSS Feed

  1. RM says:

    Gave up on Safari, just don’t like anything about it. I will try this to see if it has improved.

  2. robertobadiah says:

    I never use Safari, it sucks. Firefox is all I use.

    • Patrick says:

      Well good for you.

    • Clamman says:

      I ditched Firefox three years ago because I got fed-up with it’s moronic, out-of-date monolithic process. This causes problems like (but not limited to) continually consuming more and more memory that can be recovered only restarting the browser, an inability to tell which tab is using all the CPU and draining my laptop’s battery, an inability to tell which tab is consuming the most memory and selectively killing it, weaker security and pauses due to poor threading of the UI. Every other browser has been multi-process based for years, but for some reason Mozilla sticks to an obsolete product spends their time implementing fluffy UI tweaks that bring no real benefits.

      I did switch to Chrome for several years, but since getting a new MBP a year ago I’ve been using Safari all the time. I like the integration across all my Apple devices. I check out Chrome and Firefox once in a while, but I really don’t see what they offer to entice me to switch. Microsoft Edge in Bootcamp is the only other one that’s particularly interesting to me at the moment due to it’s native support of HEVC allowing DASH-265 playback.

    • David says:

      You never use Safari, yet you think you know anything about it? That’s like me saying I’ve never met you, but you must be an bass!

      I use both, plus Chrome and Opera. Safari is better than Firefox in many ways.

  3. Ted says:

    I believe Firefox has already invented the concept a while back, but thanks for catching up with the 21st century, Apple!


  4. cockroach says:

    It seems there is a DNS issue with this version, or maybe the app has it’s own DNS settings that I did not find. Either way loading web pages initially is slower as the domain communication is fumbling.

    I am not sure of the Webkit release and this, how they are different, etc, what’s the point. Maybe it is someones pet project? Meanwhile, iOS 9.3 is crashing and burning for tens of thousands of customers.

  5. Wharf Xanadu says:

    A purple icon. Ok then.

  6. Bon Iver Bro says:

    Unfortunately this new version of Safari has the same freezing issue on my Mac.

    I do not know what causes it, but here are the symptoms:

    – Typing in any text entry point stutters randomly

    – Beachball all over the place

    – Eventually, entire Mac freezes and requires a forced power button restart

    Has been consistent since Mac was skewed with OS X 10.11.4, never had it beforehand.

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