iOS 27.3 beta brings vertical tabs and dark mode to Safari

Apple has released the first beta builds of iOS 27.3, iPadOS 27.3 and macOS 27.3. The standout changes are all in Safari: the browser gains a vertical tab layout, Adaptive Dark Mode and tab management through Siri. All three features arrive across iPhone, iPad and Mac under the same version number, and they matter to anyone who uses Safari every day.

The betas are rolling out to developers starting today. The public release of the update is expected to land in December, so users outside the developer program may have to wait a few more weeks before trying the new features.

Vertical tabs arrive in Safari

When the new Vertical Tabs option is enabled, tabs are stacked along the left side of the browser window instead of across the top, as in Safari's traditional design. By default, tabs are shown as icons only, with the aim of making the most of both vertical and horizontal space. Users who want more context can resize the tab bar to see website titles as well, leaving the balance between screen space and readability up to personal preference.

On iPhone, the feature is found in the Settings app: go to Apps, select Safari and look for the Vertical Tabs option. On Mac and iPad, it can be switched on directly from the View menu in the Safari app. There are two different routes depending on the device, and both take only a few taps.

Vertical tabs have become increasingly common among web browsers, and The Browser Company's Arc was a major force in popularizing the layout. Arc's development was halted last year, however, and the company announced last month that it will shut the product down entirely in December. Safari building the layout into the system lands at a notable moment, just as Arc heads toward its end.

Adaptive Dark Mode for every site

For users who frequently visit sites that lack a dark theme, Apple is introducing Adaptive Dark Mode. The feature automatically applies a dark appearance to websites that do not offer dark mode support, which should make bright pages less tiring on the eyes at night or in dim rooms.

With dark mode turned on in iOS, iPadOS or macOS, visiting a site without dark theme support now brings up a new Try button. Tapping it makes Safari generate a dark version of that site automatically. Users can choose to have the feature kick in on every site by default or use it only on the sites they pick one by one, which leaves control in the hands of anyone who may not like how a particular site looks in its generated dark form.

Managing tabs with Siri

The third addition is on the Siri side. With iOS 27.3, iPadOS 27.3 and macOS 27.3, Siri can act on tabs directly, including moving, ordering, organizing and closing them. For people who work with many tabs open at once, that could cut down on the effort of tidying them up by hand.

Siri's on-screen awareness is also said to expand in a future update. That would let Siri take into account the full content of a web page rather than just the portion currently visible. This expansion is not part of the current betas and is due in a later update.