Apple Launches 'Safari Technology Preview' Browser for Web Developers

Wednesday March 30, 2016 10:19 am PDT by Juli Clover

Apple today launched Safari Technology Preview, a new version of its web browser aimed specifically at developers. Safari Technology Preview is aimed at giving developers a way to access new web technologies Apple is planning to implement in iOS and OS X, offering an early look at new developer tools, layout technologies, visual effects, and more.

According to TechCrunch, Apple's goal with Safari Technology Preview is to gather feedback from developers on its browser development ahead of launch through a method that's more easily accessible than WebKit.

safaritechnologypreview

Of course, Apple has for a long time offered Nightly builds of WebKit, the open source browser engine that today runs on hundreds of millions of devices and powers Apple's Safari. However, getting access to these builds takes a bit more effort than using the new Safari Technology Preview browser. Instead, with the new browser, its updates are distributed every two weeks by way of the Mac App Store's software update mechanism. That means it's less hassle to run a browser that features the latest advances in web technologies, including HTML, JavaScript, CSS and WebKit.

Safari Technology Preview can be run side-by-side with the existing Safari browser, and it's able to be set as the default browser on a machine. It includes local data stores for history, bookmarks, cookies, and cache, and it supports syncing of browsing history and bookmarks over iCloud. Visually, the Safari Technology Preview icon is designed to resemble the Safari icon, but it is purple in color instead of blue.

The current build of Safari Technology Preview includes several JavaScript improvements, HTML enhancements, and Web Inspector changes:

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

Safari Technology Preview can be downloaded immediately from Apple's Developer website and it will receive regular updates through the Mac App Store. While designed for developers, Safari Technology Preview does not require a developer account to download.

Tags: Safari, Safari Technology Preview

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Top Rated Comments

Fuchal

137 months ago

The best part about this for me is that the icon is purple.

Score: 16 Votes (Like | Disagree)

djang0

137 months ago

They should make this available for iOS. How are professionals using iPad Pro supposed to test their websites? If Apple doesn't take the iPad Pro seriously then professionals aren't going to use it.

This just goes to show how iPad Pro is not really a laptop replacement after all (just one example out of many). It's a marketing gimmick.

Score: 8 Votes (Like | Disagree)

macduke

137 months ago

They should make this available for iOS. How are professionals using iPad Pro supposed to test their websites? If Apple doesn't take the iPad Pro seriously then professionals aren't going to use it.

Score: 8 Votes (Like | Disagree)

redheeler

137 months ago

Will this allow me to actually close YouTube tabs and windows without crashing the entire GUI ('https://discussions.apple.com/thread/7282867') and forcing me to restart, unlike Safari? How long do we have to go before Safari can work with YouTube on recent machines with El Capitan again?

I have not experienced this once and it is not at all normal. Do you have any third-party extensions or plugins that may be causing this?

Score: 7 Votes (Like | Disagree)

Westside guy

137 months ago

I strongly suspect any actual useful feedback coming from actual developers is going to be drowned out by the cacophony coming from the hipsters / fanboys / other people with too much free time on their hands.

Score: 5 Votes (Like | Disagree)