9to5mac: macos 27.3 brings vertical tabs and adaptive dark mode to Safari

Tabs move to the side

Safari’s new Vertical Tabs option places tabs along the left side of the browser instead of across the top. They appear as icons by default, and users can resize the tab bar to show website titles.

On iPhone, the option is in Settings under Apps and Safari. Mac and iPad users can turn it on from Safari’s View menu. Vertical tab layouts have gained popularity in web browsers. Arc helped popularize the approach, but The Browser Company said it would discontinue Arc in December after ending development last year.

Dark Mode for more websites

Adaptive Dark Mode can apply a dark appearance to websites that do not support Dark Mode themselves. When Dark Mode is enabled on an iPhone, iPad or Mac, Safari displays a “Try” button on an unsupported site. Users can choose to apply the feature automatically or activate it separately for each website.

Siri can manage tabs

Siri AI Custom Actions can now work directly with Safari tabs. Users can ask Siri to move, sort, organize or close them. A future update will extend Siri’s on-screen awareness to the full content of a website, rather than only the portion currently visible.

Developer testing begins

Apple has made iOS 27.3, iPadOS 27.3 and macOS 27.3 available to developers for beta testing. The updates are expected to reach everyone sometime in December.