Sidebar and Vertical Tabs Launch in Release 136

[asafko]

Hi folks! The updated sidebar and vertical tabs are now rolled out and available to all release users on Firefox 136.

How to enable it
Go to Firefox Settings → General → Browser Layout and check Show sidebar. Then, choose the settings icon in the sidebar to customize which tools appear. You can turn on vertical tabs from sidebar settings or simply right-click on the Firefox toolbar or tab strip and select Turn on Vertical Tabs.

Firefox Settings: Browser layout

Customize sidebar options

Key improvements

✅ Horizontal tab users can now hide and show the sidebar with one click using the sidebar toolbar button.

✅ Sidebar settings have been streamlined, making customization easier.

✅ Close vertical tabs in one click without expanding them. The close button now appears when hovering over a tab favicon.

✅ We’ve removed auto-collapse behavior of vertical tabs, as it proved cumbersome for many folks. 

What’s next? 

We’re working on more improvements to enhance the sidebar and vertical tabs experience. Some top priorities include:

• Remembering your last opened sidebar panel. When you hide the sidebar and then reopen it, the last opened panel will already be expanded. We hope to ship this as soon as Firefox 137 (April 1).
• More sorting options for history and better keyboard navigation, to match the functionality of the previous sidebar version.
• Expanding vertical tabs on hover for easier navigation.

As usual, we appreciate your patience and continued use as we refine these features and experiment to help us get to a better, more polished experience. 

[Alaric]

New options are nice, but I really, really dislike the UI layout. I really just want my bookmarks on the sidebar, as I had before. But now, this update has suddenly introduced ~30% more useless wasted sidebar screen space. Why? I can remove all the other sidebar option buttons, so why do I need to see the sidebar itself just hanging out there with a single button for the only sidebar option that I want? Please, please, please let us hide the sidebar itself to reclaim this wasted screen space introduced with this new update.

This has actually driven me to make an account here and seek out a way to give this feedback here because it bothers me that much.

[JBL_in_AZ]

I have to say it.  I can't use vertical tabs as I just tried them in Firefox 138.0.1.  It's better than what I experienced when I tried it in Chrome, but not much.  I have been using the Tree Style Tab Extension for I-don't-know-how-many years.  Not only are tabs vertical, but they can be arranged in trees; you can set it to open a link in a "subordinate" tab, and you can have as many levels as you want.  If you have a tree of tabs you're not actively using, you can collapse them into a top level tree so they are out of your way.  Not quite the same as tab groups, but similar.  And there are lots of options.  This design has been around for so long I'm surprised you haven't taken advantage of it.  As long as it keeps working with the current version of Firefox (and the developer has been keeping up) I won't use anything else.  I've included snapshot of my current tabs (with some nesting) and two collapsed trees, one with 18 tabs; hovering such a tree lists lists the tabs hidden there.

[DeadKing]

Is there a way to make the bookmarks menu on the side bar floating instead of It pushing the webpage content to the side?

[dongadoya]

The bookmarks toolbar button might work for you.

[DeadKing]

Yeah I prefer that for now. But the menu in the sidebar has a search and just looks nicer.

[iodine9669]

Any plans to keep the pinned tabs styling consistent regardless of the state of the on-hover expand feature? Here's a bunch of screenshots to showcase the issue:

Expand sidebar on hover: ON

Expand sidebar on hover: OFF

[purple]

I could only use this if you bring back autohide. I need as much screen real estate as possible, especially when working on a laptop

[purple]

Also I want it so that its completely invisible until I touch the edge, just like how Zen does it.

[iesper]

Love the vertical tabs so far, but as someone with one vertical monitor, I would love to modify / set a threshold where tabs should be activated.

[davidleejy]

Firefox could consider achieving feature parity with popular vertical tab extensions like "Sidebery" (https://github.com/mbnuqw/sidebery).

What I think are possibly the four most helpful features for users managing hundreds of tabs in Firefox:

- Rename tab titles.

- Color tabs.

- Tab groups (see attached screen recording)

- Tab preview on mouse-over (see attached screen recording)

[icemessenger]

I am using both Firefox and Edge. 

Love the sidebar in Edge, so many apps like Instagram, Whatsapp, Facebook, Discord, Twitter, etc. and they can be reordered by dragging around easily. Sidebar in Opera is nice too, but far lesser apps. Chrome is the worst - no sidebar.  

Some of the issues with Firefox sidebar:

• Not all add-ons/extensions are shown on the sidebar
• No options to reorder the extensions
• Cannot hide extensions 

[tgm_1]

You guys have done a great job on the vertical tabs!

I have just one request though - with the bar on the left, tabs would be easier to close if the close button was on the left, right at the screen edge. At least, I think it would be...

[Agentvirtuel]

Hello

https://connect.mozilla.org/t5/ideas/make-closing-tabs-easier-on-sidebar-expand-on-hover/idc-p/96600
If you wish to test userChrome.css

[Shriradhakrishn]

Request to Introduce AI Sidebar in Firefox for Android

I appreciate your recent innovation in integrating an AI sidebar on Firefox desktop. I would like to request that this feature be extended to Firefox for Android as well.

Given the increasing reliance on AI tools, having an AI assistant sidebar on mobile would greatly enhance productivity and user experience. Bringing this feature to Android would reinforce Firefox’s leadership in user-focused, privacy-respecting innovation.

Thank you for considering this request.

Sincerely,
A Firefox for Android user

[Mr_n]

Vertical tabs seem like a great idea; I use Firefox containers extensively (124 containers, 2-3 tabs each, every week another 1-5 containers are added) and the names of containers in the vertical tabs are absolutely crucial to my workflow. To be able to use vertical tabs in daily driver mode I'd need to see the names (even with on-hover, but bonus points for utilising the padding between vertical tabs) of the containers to be able to switch between them faster.

Currently I just open containers menu and scroll down to a container whose tab I need to do something at and go from there (the little ">" menu position on the right of the container).

[OffensiveBias]

I really like the new sidebar and vertical tabs features. There is something strange I noticed however. The Firefox view button disappears when switching to vertical tabs. And I don’t really understand this design choice. I get that that there is some overlap with the sidebar functionality. But that overlap is also there with the ‘tabs from other devices’ button, which is there in the sidebar regardless of using vertical or horizontal tabs. Yet the Firefox view button only disappears when using vertical tabs. And some functionality is really lost there. The Firefox view menu shows you not only all tabs and tabs from other devices but also recently closed tabs and your history. I think it is a nice overview feature and one that is not completely replaced by the sidebar of vertical tabs features. I would wish this button is maintained regardless of choosing vertical of horizontal tabs.  

Edit 1: I would also suggest to maybe merge the tabs from other devices and firefox view buttons. I think that would simplify the UI without sacrificing any functionality as the tabs from other devices are already integrated into the Firefox View feature. 

Edit 2: For anyone who also wishes to have the firefox view button while using vertical tabs, there is a workaround I found for this. You can open a tab and type 'about:firefoxview' in the address bar. You will get the same menu and if you pin this tab it's almost the same as having the original button. 

[dongadoya]

That's odd. I still have the button "View recent browsing across windows and devices" that displays "Firefox View" while using vertical tabs. 

[OffensiveBias]

I'm a doofus, it moves to the right of the top bar. It had completely escaped my attention. 

[fogmachine]

I'm using Firefox to run display-only kiosks in -kiosk mode. Imagine my surprise when after an upgrade the layouts were  besmirched by the sidebar (serves me right for keeping software updated). The vertical sidebar might be great in many situations but is not useful (or even useable) in kiosk deployments.

Could Firefox add controls for the sidebar that don't require attaching a keyboard or mouse to the machine? I can think of a few ways to do it -

• a command-line option to start with the sidebar closed
• the existing -kiosk switch starts with the sidebar closed
• a parameter in a configuration file that can be edited before the system is deployed

Any of these (or something similar) would meet our needs. Please advise.

[DonReba]

I have been using the TST extension for a long time, and there are two essential features that are missing from Firefox's implementation: tab nesting and tab colouring (from the TST Colored Tabs extension).

More generally, though, I wish Firefox would focus on making life easier for extension builders, instead of competing with them. The XUL extension massacre of 2017 was tragic, and Firefox has never recovered from it.

Specifically, give the TST extension the ability to use "Send Tab to device" and let us hide the native tab bar altogether.

[hermick]

I switched to the vertical tab bar in the last month or so. It's an adjustment, but I like it because I tend to have way too many tabs open, and this makes scrolling to find them more natural.

I've recently encountered a new problem. Windows 11 has a bug where it resizes all my windows whenever I shut the lid, plug in a dock, etc. As a consequence of this (I think), Firefox is adjusting the my vertical tab bar, resizing the invisible divider so that it hides all but the top row of my pinned tabs. I can pretty easily resize it back, but I'm having to do this multiple times per hour. I've seen this on both of my Thinkpads, both of which have Windows 11.

I don't remember this happening until recently (starting in June, perhaps), and the Windows 11 issue has been happening longer than that, even occurring on my old Dell Latitude. I couldn't find mention of this elsewhere, so I apologize if this is a known issue.