Quote:Mozilla released a Firefox Nightly test build recently that includes support for vertical tabs. This new functionality is not available in regular Firefox Nightly builds, but there is a way to get that build and test it for yourself.

Native vertical tabs support is a highly requested feature. It is placed third currently on Mozilla's Connect website, just behind native tab grouping, and the restoration of PWA support in Firefox.

Vertical tabs move tabs from a horizontal bar at the top of the browser to the side. It enables better drag & drop support, sorting, hierarchical views, and better use of space on widescreen monitors or sites that limit their width.

Firefox would not be the first browser to support vertical tabs. Several browsers, including Microsoft Edge, Brave, or Vivaldi, support vertical tabs already (with Vivaldi taking the cake when it comes to customization options).

There has always been talk about introducing vertical tabs in Firefox. The last time was in February 2022, when Mozilla looked into the matter.

Vertical tabs in Firefox Nightly



The test build shows the horizontal tab bar and the sidebar at the same time by default. A click on the new "hide tab strip" button hides the horizontal tab bar so that only the vertical sidebar remains.
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