Following the release ofmacOS 27.3 developer beta 1, Apple is now rolling out the first test build for users enrolled in the public beta. Here’s what’s coming
macOS 27.3 is a big one
Contrary to macOS 27.2, it looks like Apple had quite a bit in store for macOS 27.3 and its counterparts.
In addition to expanding Siri AI to four more languages, including Traditional Chinese, Norwegian, Turkish, and Vietnamese, the system also introduces several new Safari features, including Vertical Tabs, Adaptive Dark Mode for websites, and the ability to organize and manage tabs using Siri AI.
macOS 27.3 also adds native Markdown rendering to Quick Look, allowing users to preview .md files with proper formatting instead of raw Markdown syntax.
The update also expands Siri AI’s capabilities across Apple’s own apps, allowing users to perform more complex actions in apps like Messages, Music, Calendar, Photos, and Reminders, as well as manage files and folders.
Apple is also introducing new tools for third-party developers to create advanced Siri AI integrations using Markdown-based instructions, allowing the assistant to coordinate multistep actions across different apps.
Users who enjoyed the wallpaper introduced with the new touchscreen MacBook Pro will also find a new screensaver called Pro Lighteensaver, which features light moving along the metallic-looking lines that form the word “PRO.”
Earlier this week, Apple also confirmed that macOS 27.3 will introduce new checks for potentially harmful content shared through public iCloud links. Starting with the update, files and photos shared using the “Anyone with the link” option will be checked by Apple, which may remove flagged content or take action against accounts that violate its policies.
The release build for macOS 27.3 public beta 1 is 26C5035r, which is the same as the developer build.
If you’d like to join Apple’s free public beta program, visit beta.apple.com.
Did you spot anything new in today’s beta? Let us know in the comments.
Worth checking out on Amazon
- Apple HomeView
- Apple TV 4K (2026) | Siri Remote (2026)
- Apple Watch Series 12 | Ultra 4
- AirPods Pro 3 | AirPods 5
- AirTag (2nd Generation) – 4 Pack
- MacBook Neo
- Logitech MX Master 4
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