Mozilla is planning to add support for vertical tabs to the Firefox browser. Edge introduced this feature about a year ago, allowing users to hide the tab bar that normally appears at the top of a window. Enabling this feature creates a sidebar with icons for each tab. Click on one of the icons to switch to the corresponding tab. So you get the same experience, and you get a more compact interface.
If you expand the sidebar, you’ll find it’s a more efficient way to manage tabs. Most sites have tons of white space on both sides of the screen, and in my opinion, having a vertical tab bar provides a better experience because it looks cleaner. Users with large or ultra-wide monitors may find vertical tabs a boon.
Vertical tabs have been a commonly requested feature by users of other browsers, especially in the Mozilla Firefox community, since Microsoft first introduced the feature. Currently, only a handful of other browsers, such as Vivaldi, have followed suit.
Users in the Mozilla Crowdicity community voted for vertical tabs for Firefox. This feedback portal is slow, but its activity is brisk. A product community manager at Mozilla finally responded to the request with good news. He wrote that since the request has become the community’s first thought, it has been reviewed by Mozilla’s developers. They’re looking into ways to improve tab management, and they’re looking into the possibility of adding support for vertical tabs in Firefox. Of course, this doesn’t mean the feature will necessarily be added, which is why I wrote “may” instead of “will”.
If you want to use vertical tabs now, there are alternative third-party extensions like “Tree Style Tab”, “Tab Center Reborn” and “Vertigo Tabs”. But these third-party extensions cannot hide the standard tab bar at the top.
This is because, like other programs of its kind, the Firefox browser has APIs that allow users to tweak the interface to their liking. But these APIs are limited and extensions cannot access or modify some parts of the GUI due to some restrictions. These rules are to protect users from malicious plugins that could otherwise cause damage, or hijack the browser.
Right now, these restrictions are limited to add-ons, which means there are other ways to modify the browser. Many Firefox browser users rely on custom CSS code to change the browser’s theme, new tab page, and more. So yes, you can use one of the scripts to edit userChrome.css to hide the tab bar and use an extension to access the tabs from the side panel.