Hi folks,
Over a year ago, we introduced an updated version of the sidebar that offers easy access to multiple tools – bookmarks, history, tabs from other devices, and a selection of chatbots – all in one place. As the new version has gained popularity and we plan our future work, we have made a decision to retire the older version in 2026.
Old sidebar version
Updated sidebar version
I know that changes like this can be disruptive – especially when they affect established workflows you rely on every day. While use of the older version has been declining, it remains a familiar and convenient tool for many – especially long-time Firefox users who have built workflows around it.
Unfortunately, supporting two versions means dividing the time and attention of a very small team. By focusing on a single updated version, we can fix issues across the Firefox frontend more quickly, incorporate feedback more efficiently, and deliver new features more consistently for everyone. For these reasons, in 2026, we will focus on improving the updated sidebar to provide many of the conveniences of the older version, then transition everyone to the updated version.
Here’s what to expect:
- Starting with the late Firefox Nightly 148, we have turned on the new sidebar by default for Nightly users. The new default will remain Nightly-only for a few releases to allow us to implement planned improvements, existing community requests, and collect additional feedback.
- In Q2 2026, all users of the older version in release will be migrated to the updated sidebar. After the switch, for a period of time, we will keep the option to return to the older version to support folks who may be affected by bugs we fail to discover during Nightly testing. During this period, you will still be able to temporarily switch back to the old sidebar by going to Firefox Settings > General > Browser Layout and unchecking the Show sidebar option.
- In Q3 2026, we will fully retire the original sidebar and remove the associated pref as we complete the transition.
Our goal is to make our transition plans transparent and implement suggested improvements that are feasible within the new interaction model, while preserving the speed and flexibility that long-time sidebar users value. Several implemented and planned improvements to the updated sidebar were informed by your feedback, and we expect that to continue throughout the transition:
If you’d like to share what functionality you’ve been missing in the new sidebar and what challenges you’ve experienced when you tried to adopt it, please share your thoughts here or file a bug in Bugzilla’s Sidebar component, so your feedback can continue shaping Firefox. And if you have a chance, please consider peeking at the existing metabug to see what improvements are already on our radar.
Hello, I believe this is the correct decision.
Could you also abandon the old profile system or combine the old and new profile systems?
And abandon the Firefox Focus/Klar browser?
Will there be further improvements to the sidebar, such as:
Auto-hide and auto-open the sidebar on hover when vertical tabs are not in use, for example, when history or bookmarks are expanded?
Vertical and horizontal tabs enabled simultaneously?
Support for all sidebar extensions, as well as support for widgets and opening websites in the sidebar?
So that the highlighted sidebar icon button is not displayed, because it is distracting.
Thank you!
This is great to hear, thanks!
It would also be really useful to increase the width of this scrollbar in the sidebar. It's currently tiny on 1440p resolution and really hard to grab.
It also auto-disppears after a second which is really awkward and I need to keep moving my mouse to keep it visible, which adds to the difficulty of actually clicking on it.
