Apple Releases Safari Technology Preview 121 With Bug Fixes and Performance Improvements

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 121 includes bug fixes and performance improvements for Web Inspector, CSS, GPU Process, Media, Web API, JavaScript, WebAssembly, Accessibility, and Speech Recognition.

The current ‌Safari Technology Preview‌ release is the built on the new Safari 14 update included in macOS Big Sur with support for Safari Web Extensions imported from other browsers, tab previews, password breach notifications, web authentication with Touch ID, and more.

The new ‌Safari Technology Preview‌ update is available for both macOS Catalina and macOS Big Sur, the newest version of the Mac operating system.

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.

Popular Stories

Apple Watch Ultra Night Mode Screen

Apple Watch Ultra 3 Launching Later This Year With Two Key Upgrades

Wednesday July 2, 2025 1:13 pm PDT by
The long wait for an Apple Watch Ultra 3 appears to be nearly over, and it is rumored to feature both satellite connectivity and 5G support. Apple Watch Ultra's existing Night Mode In his latest Power On newsletter, Bloomberg's Mark Gurman said that the Apple Watch Ultra 3 is on track to launch this year with "significant" new features, including satellite connectivity, which would let you...
iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro Max Battery Capacity Leaked

Thursday July 3, 2025 5:40 am PDT by
The iPhone 17 Pro Max will feature the biggest ever battery in an iPhone, according to the Weibo leaker known as "Instant Digital." In a new post, the leaker listed the battery capacities of the iPhone 11 Pro Max through to the iPhone 16 Pro Max, and added that the iPhone 17 Pro Max will feature a battery capacity of 5,000mAh: iPhone 11 Pro Max: 3,969mAh iPhone 12 Pro Max: 3,687mAh...
iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro Coming Soon With These 14 New Features

Friday July 4, 2025 1:05 pm PDT by
Apple's next-generation iPhone 17 Pro and iPhone 17 Pro Max are just over two months away, and there are plenty of rumors about the devices. Below, we recap key changes rumored for the iPhone 17 Pro models. Latest Rumors These rumors surfaced in June and July:Apple logo repositioned: Apple's logo may have a lower position on the back of the iPhone 17 Pro models, compared to previous...
iPhone 17 Pro Lower Logo Magsafe

iPhone 17 Pro's New MagSafe Design Revealed in Leaked Photo

Wednesday July 2, 2025 8:37 am PDT by
The upcoming iPhone 17 Pro and iPhone 17 Pro Max are rumored to have a slightly different MagSafe magnet layout compared to existing iPhone models, and a leaked photo has offered a closer look at the supposed new design. The leaker Majin Bu today shared a photo of alleged MagSafe magnet arrays for third-party iPhone 17 Pro cases. On existing iPhone models with MagSafe, the magnets form a...
airpods pro 2

AirPods Pro 3 to Help Maintain Apple's Place in Earbud Market Amid Increasing Low-Cost Competition

Thursday July 3, 2025 7:25 am PDT by
Apple's position as the dominant force in the global true wireless stereo (TWS) earbud market is expected to continue through 2025, according to Counterpoint Research. The forecast outlines a 3% year-over-year increase in global TWS unit shipments for 2025, signaling a transition from rapid growth to a more mature phase for the category. While Apple is set to remain the leading brand by...
Wi Fi WiFi General Feature

iOS 26 Adds a Useful New Wi-Fi Feature to Your iPhone

Wednesday July 2, 2025 6:36 am PDT by
iOS 26 and iPadOS 26 add a smaller yet useful Wi-Fi feature to iPhones and iPads. As spotted by Creative Strategies analyst Max Weinbach, sign-in details for captive Wi-Fi networks are now synced across iPhones and iPads running iOS 26 and iPadOS 26. For example, while Weinbach was staying at a Hilton hotel, his iPhone prompted him to fill in Wi-Fi details from his iPad that was already...
iOS 18

Apple Releases Second iOS 18.6 Public Beta

Tuesday July 1, 2025 10:19 am PDT by
Apple today seeded the second betas of upcoming iOS 18.6 and iPadOS 18.6 updates to public beta testers, with the betas coming just a day after Apple provided the betas to developers. Apple has also released a second beta of macOS Sequoia 15.6. Testers who have signed up for beta updates through Apple's beta site can download iOS 18.6 and iPadOS 18.6 from the Settings app on a compatible...

Top Rated Comments

aesc80 Avatar
57 months ago
Posting in here so Safari Beta feels appreciated.
Score: 5 Votes (Like | Disagree)
Kobayagi Avatar
57 months ago
I've been using Safari for more than 10 years, but the latest version is horrible honestly.
It has become very, very slow while I haven't changed anything about my setup or the way I use Safari. I also haven't added any new extensions. Same Mac, same everything. It also runs like crap even without any extensions, clear cookies, cache etc.

Web pages just keep freezing and make me wait for more than 10 sec for them to respond, double taps to zoom with the Magic Mouse make it freak out and lag so much. It makes my MacBook Pro freak out and the temps go high and so does the fanspeed...

I still use Safari because it's convenient with all the iCloud sharing between my iPhone and iPad. I hate to say it, but Chrome runs so, so much better, regardless what Apple's fancy speed bragging comparisons say. But I also don't wanna switch with everything to Google for obvious reasons.
Score: 4 Votes (Like | Disagree)
Rob_2811 Avatar
57 months ago

Hello, Facebook! ;)

Joke aside, what makes you say so? What kind of requirements do you have for Safari to have disappointed you? Genuinely curious.
I just experience a lot of slow loading pages and hangs. Almost every time I can drop the URL in to Firefox and the page loads instantly.

I mostly used Firefox anyway for the superior dev tools but would occasionally use Safari when on the go for the better battery life, I gave up on Safari completely about six months ago.
Score: 3 Votes (Like | Disagree)
steve333 Avatar
57 months ago

I've been using Safari for more than 10 years, but the latest version is horrible honestly.
It has become very, very slow while I haven't changed anything about my setup or the way I use Safari. I also haven't added any new extensions. Same Mac, same everything. It also runs like crap even without any extensions, clear cookies, cache etc.

Web pages just keep freezing and make me wait for more than 10 sec for them to respond, double taps to zoom with the Magic Mouse make it freak out and lag so much. It makes my MacBook Pro freak out and the temps go high and so does the fanspeed...

I still use Safari because it's convenient with all the iCloud sharing between my iPhone and iPad. I hate to say it, but Chrome runs so, so much better, regardless what Apple's fancy speed bragging comparisons say. But I also don't wanna switch with everything to Google for obvious reasons.
I have the same issues as do many others, I have read forums here and on reddit about the problem. Do you also get a spinning beach ball when clicking on the bookmarks menu?

Interesting, you need to look elsewhere for what is going on, it’s not safari which works great
Yeah, it is Safari. See above. Worked great before Big Sur, works like garbage afterwards.
Apple isn't even acknowledging the issue. I opened a thread on Apple's support forums and they give the usual do this do that that fixes nothing, then they just left
Score: 2 Votes (Like | Disagree)
steve333 Avatar
57 months ago

If it was safari, I would have the problem too. So no, you are wrong, it is not safari. On the other hand, after the big chrome security issue recently, my safari would not load without crashing. I did a clean install, deleted chrome altogether and I am running completely fine. So not safari, not necessarily chrome, but fixed
Why are you having so much trouble believe this when others are having the issue with Safari (and Safari only) after upgrading to Big Sur?
Obviously there is an issue, could be a compatibility issue with certain machines, maybe certain chips or graphics cards.
Score: 2 Votes (Like | Disagree)
steve333 Avatar
57 months ago

it is simple, if it was safari and safari alone, it would be a universal problem, but it is not. why are you having so much trouble understanding that, it is a simple concept. Now, there may be something going on with people, something specific to their machines certain extension, even malware, even old libraries impacting the performance, but they are not simply Safari. Do a clean install, clean up all the crap, and it will work fine, it did for me.
If it happening only with safari, then it is a safari issue. Everything else, including firefox, works fine.
Score: 2 Votes (Like | Disagree)