Apple Releases Safari Technology Preview 129 With Bug Fixes and Performance Improvements

Wednesday August 4, 2021 10:46 am PDT by Juli Clover

Apple today released a new update for Safari Technology Preview, the experimental browser Apple first introduced in March 2016. Apple designed the ‌Safari Technology Preview‌ to test features that may be introduced into future release versions of Safari.

Safari Technology Preview Feature
‌Safari Technology Preview‌ release 129 includes bug fixes and performance improvements for Web Inspector, CSS, Scrolling, Rendering, WebAssembly, Web API, Platform Features, IndexedDB, Media, WebGL, and WebCrypto.

Apple says that on macOS Big Sur, this release requires enabling the GPU Process: Media option from the Experimental Features setting in the Develop menu. Turning on the option addresses issues with streaming services.

The current ‌Safari Technology Preview‌ release is built on the new Safari 15 update included in macOS Monterey, and as such, it includes several Safari 15 features. There's a new streamlined tab bar with support for Tab Groups to organize tabs, along with improved support for Safari Web Extensions.

Live Text allows users to select and interact with text in images on the web, but the macOS Monterey beta and an M1 Mac is required. There's also Quick Notes support for adding links and Safari highlights to remember important information and ideas.

Other updates include WebGL 2 and new HTML, CSS, and JavaScript features.

The new ‌Safari Technology Preview‌ update is available for both macOS Big Sur and macOS Monterey, the newest version of the Mac operating system that's set to release this fall.

The ‌Safari Technology Preview‌ update is available through the Software Update mechanism in System Preferences to anyone who has downloaded the browser. Full release notes for the update are available on the Safari Technology Preview website.

Apple's aim with ‌Safari Technology Preview‌ is to gather feedback from developers and users on its browser development process. ‌Safari Technology Preview‌ can run side-by-side with the existing Safari browser and while designed for developers, it does not require a developer account to download.

Tag: Safari Technology Preview

Popular Stories

Home Hub Command Center with Dome Base Feature

Apple Smart Home Hub to Feature iMac G4-Style Design

Wednesday September 30, 2026 4:36 am PDT by Hartley Charlton

Apple's long-rumored smart home hub will have an iMac G4-style design and a host of unique features, Bloomberg's Mark Gurman reports. The smart home hub is said to feature a square 6-inch display, with variants that can be placed on a countertop or mounted on a wall. It features a single FaceTime camera on the front, with microphones and speakers in its connected base. Gurman described the...

• 193 comments

Three New Apple Smart Home Products Coming on October 13

Wednesday September 30, 2026 4:04 am PDT by Hartley Charlton

Apple plans to introduce a series of new smart home products on Tuesday, October 13, according to Bloomberg's Mark Gurman. Apple reportedly plans to debut its long-awaited smart home hub device, a new HomePod mini, and a new Apple TV on the date. The new HomePod mini and Apple TV are set to retain their existing designs, but tout faster chips to support Siri AI. The new HomePod mini will...

• 56 comments

New Apple TV 4K Leaked

Friday September 25, 2026 8:16 am PDT by Joe Rossignol

MacRumors contributor Aaron Perris has uncovered an image file from Apple for an unreleased Apple TV 4K, suggesting that a new model will finally be released soon. The image is specifically for an "Apple TV 4K (4th generation)" model. Apple TV 4K (4th generation) image (on a gradient) The image reveals that the Apple TV will have the same external design as the current model, with all of its...

• 192 comments

Top Rated Comments

diamondsw

67 months ago

Am I the only one who uses the Favorites Bar? It looks really bizarre being under the tab bar now.

Score: 6 Votes (Like | Disagree)

chucker23n1

67 months ago

The release notes no longer say that tab groups don’t sync.

But, it looks like tab groups don’t sync.

Score: 2 Votes (Like | Disagree)

abhibeckert

67 months ago

I really want to use Safari but no chromium engine kills it for me. I'm not saying you should use Chrome, just a chromium browser: Brave, Edge etc. Firefox is slow on some sites, while chromium browsers are fast.

And every test I've ever seen shows Safari browsers are faster. As someone who uses both, that's been my experience too. It's a noticeable difference.

Also Chrome is not the battery enemy it used to be. Lots of improvements the last couple of months

Forbes ran an article from earlier this year showing Chrome with an "Energy Impact" number 10x higher than Safari. It also mentioned the test device (M1 MacBook Pro) gets warm running Chrome but stays cold with Safari... which means Chrome is likely pushing the CPU hard enough that it will drop the clock speed to manage temperatures on some hardware. When that happens it will start getting *really* slow (I'm guessing this is why Chrome feels noticeably slower than Safari for me).

I'm sure Chrome has improved, they're working on it continuously, but I doubt it's improved that much.

And Safari isn't sitting still either. Safari 15 is even faster and uses less power than Safari 14.

Score: 2 Votes (Like | Disagree)

jabbr

67 months ago

Weird thing is that my setting was reset after updating, since I was using the compact.

Yeah, makes we wonder if they will completely ditch the idea upon release. I hope not... I like the little bit of extra vertical space.

Score: 2 Votes (Like | Disagree)

ericfroemling

67 months ago

Looks like they removed the option to use the new combined layout for tab bar. The tab bar is always separate in this release.

It looks like it's just been moved to Preferences -> Tabs instead of being under the View menu.

Score: 2 Votes (Like | Disagree)

Silverlox

67 months ago

I might have time to help, if you have a particular site that you absolutely need dark mode, I will be glad to look at it as long they are no restricted area where I cannot test the CSS because of lack of access I will edit and share the CSS so you can apply it using Cascadea which is also not free.

Thanks for the offer, its not too big a deal and I can live with some in dark mode so Thanks but I'll leave it alone.

Score: 1 Votes (Like | Disagree)

Read All Comments

Apple Releases Safari Technology Preview 129 With Bug Fixes and Performance Improvements

Popular Stories

Apple Smart Home Hub to Feature iMac G4-Style Design

Three New Apple Smart Home Products Coming on October 13

New Apple TV 4K Leaked

Top Rated Comments

Next Article

Videos

Guides

Upcoming

Other Stories