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.

[zombieman]

I wish this "Nova" thing was more about undoing to changes that the Proton UI implemented. Didn't like Photon either or even Australis before that if I'm honest. "Softer tab shapes" is absolutely NOT want I want. I want hard edges even between inactive tabs. I want CLARITY on where tabs are and ideally tabs to be below the address bar and can we put an end to this thing about getting rid of menu and title bars. I *ALWAYS* turn those back on with EVERY install of Firefox. Those are the best UI feature of Firefox over Chromium browsers.... Oh and I'd quite like a proper preferences window back please... And a downloads window...

[AstrobotNautics]

I do find it strange that 'themes and customisation' doesn't give options to alter tab styles. It alters the background colour, but why hasn't 'appearance' also allowed you to customise tab shapes through the years...
Waterfox gives you options, but it is only between Nova, Photon and Proton, so I think you're a bit out of luck there. 

[NoName1231]

It's horrible and I was not asking for it. At least give an option with square tabs. The grey one without gradient is alright but the round tabs still annoy me so much, I consider changing the browser altogether. 

[AstrobotNautics]

Try Floorp or Waterfox as alternatives, they are generally a bit more stable when it comes to design choices. Waterfox still implemented Nova, but it's much easier to turn off. Floorp has just disabled it outright for as long as Photon or Proton are supported, also it comes with Red Pandas.

[dftf]

1. You can undo most of the new UI changes by:
Typing about:config then pressing ENTER
Accept any warning shown
Search for nova
Double-click on "browser.nova.enabled" to set it to "false"

2. Install the previous "Proton" theme from here:
https://addons.mozilla.org/firefox/addon/firefox-proton/ 

3. Look into Firefox alternatives, such as "Floorp", "Librefox" or "Waterfox".  Some will also have adopted the new "nova" UI, but allow for easier reversing of it

[mlwasteland]

Can you make a less sensitive skin for those that appreciate efficiency and fewer wasted pixels? Something more pragmatic? Or, would that offend too few people?  

[dftf]

1. Undo most of the new UI changes by:
In the URL bar, type about:config then press ENTER
Accept any warning shown
Search for nova
Double-click "browser.nova.enabled" to set it to "false"

2. Install the previous "Proton" theme from here:
https://addons.mozilla.org/firefox/addon/firefox-proton/ 

3. Or explore other themes here:
https://addons.mozilla.org/firefox/themes/ 

[NoName1231]

Thanks, but if I have to put in any effort, it's shifting my bookmarks to another browser...

[dftf]

You're free to move to a different browser any time, of course.

Though that will likely take more-time than the 30 seconds at-most to make those changes, so maybe try them first?

[F_firefox]

It's fugly. I've stuck with Firefox through a bunch of BS, but making it visually hideous on top of the AI bull**bleep** and data collection by default? F right off; F Firefox.

[dftf]

If you haven't already, you can undo most of the new changes by:

Typing about:config in the URL bar, then pressing ENTER
Accept any warning shown
Search for nova
Double-click "browser.nova.enabled" to set it to "false"

[Gonzo-Goliath]

How can I undo all the UI design changes from the last update? It looks absolutely rubbish now with those jagged tabs and menus!!! I’m not going to spend 100 hours on custom CSS just to get the previous interface back!

[Gonzo-Goliath]

How can I undo all the UI design changes from the last update? It looks absolutely rubbish now with those rounded tabs and menus!!! I’m not going to spend 100 hours on custom CSS just to get the previous interface back.

[dftf]

In the URL bar, type about:config then press ENTER
Accept any warning shown
Search for nova
Double-click "browser.nova.enabled" to set it to "false"

That will undo most of the changes

[Gonzo-Goliath]

Thank you very much, the old user interface is much clearer and more minimalist. 😍

[Elfener]

Is this why my browser chrome looks like those AI slop websites rather than my system theme like it used to?

Who decided this was a good idea?

[dftf]

To mostly-undo the recent change:

URL bar -> about:config -> ENTER -> accept warning -> search nova ->
double-click line "browser.nova.enabled" to change it to "false"

You can install the previous theme from here:

https://addons.mozilla.org/firefox/addon/firefox-proton/ 

[ZCi2Fuxr3Hvj]

The containers tabs are hard to use now, I tried all combinations of available colors and even after setting a theme with high contract background between 4 containers you can't avoid having 2 confusingly close on a regular cheap lcd laptop screen. Don't like the esthetic part either but whatever.

[dftf]

These steps will mostly-undo the recent change:

URL bar -> about:config -> ENTER -> accept warning -> search nova ->
double-click line "browser.nova.enabled" to change it to "false"

And you can get the previous themes here:

https://addons.mozilla.org/firefox/addon/firefox-proton/ 

[HstsLover]

PLEASE stop changing the design, not only is it pointless but opening your browser and finding a completely different UI is jarring.

Pick a design and keep it that way, if users aren't satisfied then they can use themes. If you want to give it a new skin then just make a new theme so you don't disrupt users that have already picked one themselves.

[dftf]

To reverse most of the recent change:
URL bar -> about:config -> ENTER -> accept warning -> search nova ->
double-click line "browser.nova.enabled" to change to "false"

You can also install the previous theme here:
https://addons.mozilla.org/firefox/addon/firefox-proton/ 

⚠ The ability to reverse Nova may end in Firefox v161, due for release November 24, 2026
Refer to: https://bugzilla.mozilla.org/show_bug.cgi?id=2071454 

[Flame_ONeill]

It looks awful and it's slow.  Fix it.

[dftf]

To mostly-reverse the recent change:
URL bar -> about:config -> ENTER -> accept warning -> search nova ->
double-click line "browser.nova.enabled" to change to "false"

You can also install the previous theme here:
https://addons.mozilla.org/firefox/addon/firefox-proton/ 

⚠ The ability to reverse Nova may end in Firefox v161, due for release November 24, 2026
Refer to: https://bugzilla.mozilla.org/show_bug.cgi?id=2071454 

[yaceq]

You destroyed Firefox with this update. I have to restart it 2 -3 times a day because sites don't load. After restart it's ok. Revert all the changes you've done. They're totaly pointless.

Even now, I had to restart Firefox to add this comment!!!

[dftf]

If sites aren't loading, it's probably an extension causing the issue -- a lot of people in the past two days have had loads of issues with YouTube, and the Ghostery extension was the cause.

See if there are any updates for your extensions:
Menu  ->  Extensions and Themes  ->  click the ⚙ icon  ->  Check for updates...

If any get updated, fully-close all Firefox windows, and bring a new one up.

If you still have issues, a custom DNS server you use might be having issues.

Menu  ->  Settings  ->  type DNS into the search box  ->  under "DNS over HTTPS", click "Custom settings"  ->  check the settings there (e.g. click "Custom" and pick a different provider)

[yaceq]

I've been using Firefox for 20 years and have never experienced something like this. I don't use this extension and all mine extensions are up to date. I use cloudflare DNS. 

This loading problem is very strange because when it appears page loads but for example any button doesn't work. it's on every page after 1st appear. Only restart helps but only for some time when it appears again. 

[dftf]

I'm not having such issues here on the 157.0 version, and cannot see any widespread reports of this so not sure what else might be your cause.

Maybe try backing up your current Firefox data:
Menu -> Settings -> Accounts and Synchronisation -> Backup

Then create a new profile
Menu -> Settings -> Profiles -> Settings -> Manage Profiles -> Create a profile

Then when you're in that new profile, test the same websites

If the issue is resolved, import your data back in:
Menu -> Settings -> Accounts and Synchronisation -> Restore your data

If not, you can always change back to your original profile, with all your data still there

[donburi]

The new border highlight on the active tab is incredibly distracting and calling too much attention to itself.

[dftf]

If you haven't done so already, use these steps to reverse most of the recent change:
URL bar -> about:config -> ENTER -> accept warning -> search nova ->
double-click line "browser.nova.enabled" to change to "false"

You can also install the previous theme here:
https://addons.mozilla.org/firefox/addon/firefox-proton/ 

⚠ The ability to reverse Nova may end in Firefox v161, expected Nov 24, 2026
https://bugzilla.mozilla.org/show_bug.cgi?id=2071454 

[p_n]

---

@dftf wrote:

⚠ The ability to reverse Nova may end in Firefox v161, expected Nov 24, 2026
https://bugzilla.mozilla.org/show_bug.cgi?id=2071454 

---

Oh, so it's time to consider switching browsers. Maybe that's the goal... to kill the Firefox project because it costs Mozilla too much.

[dftf]

Google pays Mozilla something like $500million a year to keep Firefox afloat, as then in browser anti-trust hearings they can go "nuh-uh your honour, Firefox exists".

If Firefox suddenly ceased to exist, where else will Mozilla get any money for?  With most e-mail now being web-based, and Microsoft looking to abandon the classic "Outlook" by the end of this decade in-favour-of the free "Outlook (new)" in Windows, I cannot see any company ever donating purely due to Thunderbird.

And beyond those two products, what else does Mozilla have? 🤔

[nubbyv2]

I think the browser feels a little snappier so far.

From a vertical tabs user: I actually prefer the pill shape tabs. However, the spacing is too big and makes it more difficult to select tabs now. I can put my mouse cursor between two tabs and there is still space between the text I am trying to choose. The option to remove the vertical tab scrollbar should be available though. I also think the gradient fading on the right side of the tabs should either be shrunk more horizontally or removed.

[Maxip]

are the random crashes solved instead having now rounded cornors?

Seriously I cannot even put into the Adressline any website url anymore.

Why are you doing that?

[ProtoDan]

Sucks so bad

[DarkMODE]

I don't really care about designs but can I have my dark mode back though? like the previous black dark, not this stupid gradient of blue-orange.

[RCocks]

Please please stop messing with my UI.

I'm not change resistant, but I've had a similar look for decades, every few years we go through a cycle where Mozilla tries to force a change, then backpedals it.

Please stop doing that. It's so tiring. New tabs merge and blend together, are hard to read, the click areas look unfamiliar.

I just want to use my browser without thinking about my browser.

[brad12345]

New design is terrible. No one asked for colors and certainly not a purple/pink gradient. At least let us pick our colors, including just plain old white again. All of the color option themes are too much color.

[shadowhunterxyz]

i decided to make an account just to give me thoughts on this update.

i hate it, bring back rectangle tabs, these ovals suck

[MozillaUpsetsMe]

You can type this into your address bar like you're going to a website:

"about:config"

Search up "browser.nova.enabled" in the menu that appears and click the little double arrow to the right to disable the new look (and maybe other things they added recently. im not a computer person but this turned off the new themes for me)
If you toggle that to "false" it will get rid of the stupid new oval tabs.

[asdf_]

I don't understand how Mozilla can be so utterly out of touch with its user base. Do you guys do zero user research before launching something like this? Is this just because Google pays for everything and you have zero accountability to any real user? How can your organization be this dysfunctional and jump through such hoops to ruin your main product like this? Your entire management chain needs to be let go.