ZDNET’s key takeaways
- Safari developer beta release notes show several new features in testing.
- Appearance changes to Safari allow for more customization in Apple’s browser.
- Siri AI will have more access to apps, completing more complex tasks.
Developer betas for MacOS 27.3, iPadOS 27.3, and iOS 27.3 are here, with a few major upgrades to the Safari browser. Vertical tabs, adaptive dark mode, and deeper Siri AI integration are on the way to the public, but are first in beta for testing.
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Siri AI is expected to be further woven into Music, Messages, Photos, Calendar, and Safari. Adaptive dark mode will allow for any website to be viewed in dark mode, even if the site doesn’t support it. Finally, vertical tabs are pretty straightforward, enabling vertical navigation and drag-and-drop tab reorganization.
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Here’s what you can expect when the software goes public in mid-December.
Siri AI makes more appearances
Siri AI gains more access to your Apple devices, allowing more cross-app functionality and the ability to execute complex, multi-step tasks within your apps.
According to 9to5Mac, you can ask Siri AI to create a playlist in Music and save it to your library, request messages to be scheduled for a later send, organize and label photos, and create a detailed calendar invite — all with your voice.
The same reporting also states that Siri AI features will appear in Maps, Weather, Shortcuts, and Notes, signaling that an AI-supercharged Siri will live in every crevice of your Apple devices.
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I’m not one to complete tasks like the ones mentioned above on my iPhone — I’m far more likely to do them on my MacBook Air, since I associate the laptop with productivity. Every blue moon I’ll rearrange my entire Apple Music catalog, every month I fill out my calendar, and sometimes I’ll go through Photos and try to organize it. I can see myself automating certain steps in these tasks, and I’m excited to try it.

A democracy on dark mode
A WebKit blog post details that adaptive dark mode is coming to Safari, how it will work, and what users can expect. According to the post, 40% of web page loads are from dark mode users, but only 10% of web pages natively support it.
I’m particularly excited about this feature, as I set my Apple devices to automatically enable dark mode at 7 p.m. to encourage a more relaxing evening scrolling vibe, especially while reading. I read a lot on my MacBook, and in a dark room, a bright page can feel too bright, but dimming my laptop’s display doesn’t quite do the trick.
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The WebKit blog post states that adaptive dark mode uses “a color matrix to invert the luminosity of colors while preserving hue” and distinguishes between when a page’s color is purely decorative and when it carries substantial meaning, to ensure the user experience remains consistent between light and dark modes.
Vertical tabs for the win
Vertical browser tabs aren’t a new concept, but they’ll soon be new to Safari. I see the value in vertical tabs: a list view is easier to scan, web page titles aren’t smushed when several tabs are open, and they’re particularly useful when you’re working on a widescreen monitor.
Many people who spend hours using their Mac or MacBook may find this upcoming feature useful. I do believe that Safari is the superior browser for personal use, given its integration with your Apple devices, especially with features like Handoff.
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However, I do have one major gripe with vertical tabs: they’re usually locked to the left panel, and I prefer the right. If Safari allows this customization, I’ll seriously consider switching from horizontal tabs.