The new Firefox design lands in today. This is what you can expect

[AshleyT]

Firefox has evolved significantly over the past year and now, its look has evolved too. 

The design begins rolling out today, with Firefox 157, bringing a cleaner, more cohesive , and more adaptable experience. It is still the Firefox you know and trust, with the same commitment to independence, privacy, customization, and user control. 

The Mozilla Connect community has helped shape this work from the beginning by sharing feedback on the early designs, tested the experience in Nightly starting in July, filed bugs, and shared with us what worked and what didn’t.

Here’s what landed today.

A cleaner, more cohesive design

• Softer tab shapes
• Redrawn icons that hold up better across light and dark themes
• Rebalanced spacing throughout the interface
• A refreshed color palette featuring the glow of the active tab, deeper purples, and warmer light tones

The updated design brought bolder color choices to Firefox — and your feedback made clear that opinions on browser color run the full spectrum. In response, we created additional themes, accessible through add-ons and a new theme picker off Firefox Home, so you have greater control over how Firefox looks. 

More ways to make Firefox yours

Firefox is becoming more customizable, giving you more ways to shape the browser around how you browse. These options include:

• A new theme picker in the customization panel on the Firefox Home page. Additional community themes remain available through about:addons.
• New Firefox themes and wallpapers
• A dedicated space to pin and organize shortcuts so sites you use all the time stay put.
• Compact Mode for a denser browsing experience

Compact mode now officially supported!

Compact Mode is now available as its own dedicated setting. It will also switch on automatically on smaller screens, reducing the space between interface elements so more fits on the screen.

This is one of the clearest examples of how community feedback shaped Nova. Many of you told us that maintaining a denser interface was important, and we listened.

Faster performance

The refreshed experience also includes improvements to Firefox’s startup, page-loading, and scrolling speeds.

Frequently asked questions

Will my existing themes and add-ons continue to work?

Themes and add-ons should continue to work. Nova is built on the same Firefox foundation, and the extension and theming architecture has not changed.

Will my userChrome.css customizations continue to work?

Some customizations may require minor adjustments, depending on how closely they rely on element names or layout structures from the previous interface. 

But keep in mind that Mozilla does not officially support customizations made through userChrome.css. They can cause unexpected behavior or even break Firefox, and future updates may affect them as Firefox continues to evolve. If you choose to use userChrome.css, please proceed carefully.

You can learn more in Firefox advanced customization and configuration options.

Can I opt out of the update?

The new Firefox design becomes the default experience starting with Firefox 157. However, you have several ways to adjust how Firefox looks and feels, including Compact Mode, themes, wallpapers, and New Tab customization. 

Keep shaping Firefox with us

Nova may be shipping today, but the work doesn’t stop here. Many of these updates grew directly from the bugs you filed and the conversations you started while the design was being developed.

Update to Firefox 157 to try the refreshed experience, then let us know what works well and what could still be improved. Your feedback will continue to help shape what comes next.

[LaiLaiHei]

Thank you so much. The design still looks awful (I think an UI UX school dropout designed it) but at least now the ridiculous rounding is more tolerable.

[Blah]

You absolute legend. Actually looks a Firefox browser again after following your suggestion!

[Helion]

Thaaaannnnnk !!!! from my eyes ‌‌😎

That was an undesired round update 😱 😩😡

@mozilla:

Compact is nice ‌‌👍

Old logos are nices 👍 but need to apply everywere 👎

No to round stuff everywere ‌‌👎

No to default theme, 👎 I just want the colors I already choose in Windows

And stop with purple go back to blue and orange plz 

[bfive]

fantastic. thank you

[lycheelyviathan]

TY legend

[Thullin]

dude thanks for putting this out there.... i need the new changed sucked but didn't realize just how blurry it made all the icons and such until i clicked between disabled and enable.

how can they say they improved the UI when in fact making things more blurry? 

[WatsonMcRotch]

Complete and utter legend right here. 

[Classy-Classic]

Nope. Didn't change to the old UI.

[dftf]

Has worked for probably over 100 people now... try it again

Remember it only applies to the 157.0 version of Firefox; if you haven't yet had that update, and are still on the 156.0 release, you won't have the new look yet, so that setting won't look any different.  Go to Menu > Help and Report > About Firefox to see which version you're currently on, and trigger an update to happen

[Yvonne]

I hate the rounded corner tabs that have a red outline.  It looks like there's an error on that tab.  Please go back to the current tab just being highlighted in white.

[Nemiz]

Neither do I. It looks so yesterday, so appleish, so eager to please and above all so unneeded. Don't get me wrong, I am grateful for the great work of the Mozilla Team but I really wish they would concentrate on performance and security. 

[SodaPop]

Try Vivaldi, for real - I switched and my browser looks like a browser again and it works great!

[jonblazeson]

Unfortunately, Vivaldi does not have containers and that's a deal breaker for productivity. Let me know if they adopt it, because I would switch if they did.

[SodaPop]

I thought workspaces have the same functionality?  I don't know - I'm not sure what you are using your containers for, but I have been using workspaces in Vivaldi.  I have a different workspace for every category; I switch back and forth from a drop-down menu next to my address bar.

[cadwellm]

The Floorp browser has containers. I use it and like it a lot.

[anonymousfox]

I am really not a fan of this UI refresh. The color bars added by multi-account containers look super awkward now, but even if that were not the case, this design iteration feels much less polished than the previous one. I wish I could go back.

[dftf]

Not sure what OS you use, but assuming Windows, you could download the ESR release of Firefox from here (https://www.firefox.com/en-GB/download/all/desktop-esr/), the latest being 153.4.0, uninstall your current Firefox, then install that one.  That will then reverse the change, and I believe will get updates until next October.

You may want to check if you use any new features introduced between then (in Firefox versions 154, 155 and 156), as you'll obviously lose those in the 153 ESR, as the ESR releases only get security updates and bug-fixes after release, but rarely any new features

[ent1]

Shouldn't be on the user to have to do all that.  This is on Firefox.  The user shouldn't have to work around a horrible design force fed to us.  Firefox needs to revert this garbage ASAP.

[dftf]

Sure, but we know they're not going to, so at least what I've suggested is a viable workaround which may buy around a year of the old UI for them

[verydispleased]

They seem not to want users. I though with new management "unwise" changes would stop, unfortunately not needed changes for changes sake continue. Bad. Very bad. Joke of a changes to UI, no rounded tabs, no colorful - how to you call it, the upper  thing between web adress and the top. No. No. No. No. Waste of developer time, money, resources. If you must make such changes optional. My patience with Firefox is lower and lower by every such not needed unwise update. And I am long time user!

[Agentvirtuel]

Bonsoir

An subject https://support.mozilla.org/en-US/kb/understanding-depth-profile-installation
https://support.mozilla.org/en-US/kb/dedicated-profiles-firefox-installation#w_what-happens-to-my-pr...

[cmcallister]

> I wish I could go back.

In `about:config` set `browser.nova.enabled` to `false`

[Amarok]

OMG THANK YOU THANK YOU!

[Classy-Classic]

Perhaps this doesn't work on Mac? I still have the new ugly UI.

[TexanTom]

worked for me on MacOS 26 and 27.

[dftf]

Hi Mozilla.  In the new look in the v157.0 stable release, the "Bookmarks" in the side-panel is broken: when you switch to the "Bookmarks" section, there is no down-arrow / down-chevron to change section again:

To fix this, type about:config in the web-address bar, then press ENTER.  Accept any warning, if shown.  Type updatedb into the search box, and you should see sidebar.updatedBookmarks.enabled appear.  Double-click that line to change it from "false" to "true".  The down-arrow should then be back!

[dftf]

Apparently this is a known-issue the developers are aware of:

https://bugzilla.mozilla.org/show_bug.cgi?id=2076296

[ehandrich]

and instead of fixing known issues they force an ugly blurry UI on us.

[JappeOdB]

Hi, can you please make the new UI optional? These rounded corners are too weird.

[dftf]

To revert it, type about:config in the web-address bar, then press ENTER
Search for nova and on the line "browser.nova.enabled", double-click it to change it to "false"

[ETEcco]

Thank you, you're a hero.

[ilya-ep]

The world needs heroes like you!

[MZconn]

Mozilla's September 2026 GUI redesign is incredibly bad and, worse yet, totally unnecessary. How did this unfortunate mistake happen?

[dftf]

Intentionally, as clearly someone had to design it, and sign off on it.

To revert it, type about:config in the web-address bar, then hit ENTER
Search for nova and on the line "browser.nova.enabled", double-click it to change it to "false"

A future Firefox version will eventually stop that setting from working though, or just remove it

[verydispleased]

Sorry to say but it seems they have way too much money, when they can spend time on not needed, bad, totally unnecessary UI changes. If changes to UI they have to be optional, that is UI 101. Please! Oh, please!

[gbjbaanb]

They were told. The Nightly feedback forum is almost universally critical of the change.

https://connect.mozilla.org/t5/discussions/take-project-nova-for-a-spin-in-nightly/td-p/131273

[Torcer]

Not a fan of the new UI changes. The rounded corners look off, and having a color gradient added to the default Dark Mode Theme is distractingly annoying. I cannot find how to disable the color gradient. At the very least the new changes should be it's own separate theme, and the old look could be a 'Classic' theme if you insist upon the changes.

[dftf]

In the address / location bar, type about:config
Press ENTER
Accept the warning, if shown
Search for nova in the search box
Double-click the "browser.nova.enabled" line to change it from "true" to "false"

The UI change should get reverted. In a future Firefox update, this setting will be removed, at which point reverting back from the new UI won't be possible

[tykysCZ]

thx for this, the ugly **bleep**les new UI 🤢

[coldharmonics]

This update is objectively worse, relying on thin lines which clutter the ui. Preexisting themes have been overridden, and switching back to them reveals just how difficult it can now be to tell which tab is selected. Furthermore, there's no reason to add ambiguity between tabs and buttons, a change which permeates across the browser and its settings. If you're going to keep copying other browsers, you might as well copy the right things from them.