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.

[SkipJacobson]

Thank you. Ended up on this page specifically because this update drove me insane and I went hunting for info on how to change the tabs back

[ThirdEyeBlind]

Why is this hidden away in about:config settings? They should make this VERY easy to revert back. It's absolutely atrocious and a huge waste of space. I don't mind change but this change has gotta be vibe coded. Sorry to the people who worked on this, but really a way to easily disable/toggle this would have gone a long way towards making this change acceptable instead of shoving this trash down our throats.

[BruceLeeroy]

@dftfTHANK YOU!!!! ❤️

[Ghostty]

i love you so much

[dftf]

Can people here not see any-other replies or something?  This is being asked like 4-5 times an hour at this point! 🙃

Anyway:

Type about:config in the address bar, then press ENTER
Accept any warning shown
Search for nova
Double-click the line "browser.nova.enabled" to set it to "false"

[Onkel_Tom]

THANK YOU !!!!!!!!!!!!!!! .... set everything with NOVA in it to false --> finally my Youtube Tabs are loading in less than 1/4 of the time before, performance increased significantly and it doesn`t look like crap anymore ^^

[dftf]

---

@Onkel_Tom wrote:

"... finally my Youtube Tabs are loading in less than 1/4 of the time before"

---

That's actually probably just a co-incidence.

You probably use the "Ghostery" extension, and they were causing massive slowdowns on YouTube.  In the time since, they'll have pushed-out an update to fix it.

So that one isn't on the Firefox team

[Leodolon]

How did you revert the ui? its so ugly

[dftf]

Type about:config in the web-address bar, then press ENTER
Accept any warning shown
Search for nova
Double-click the line "browser.nova.enabled" to set it to "false"

[Classy-Classic]

This did not work for me. No change in the UI.

[Classy-Classic]

Finally worked.

[vy987]

Why the hell is this so hard to find? Users shouldn't have to go into settings that Mozilla itself considers advanced enough to warn us before fiddling with, just to make the browser look how we want it to.

[Gena]

The update is absolute crap.

[nomisum]

i fully second this notion

[Thullin]

Agree... this change was not needed.

[niwa]

Couldn't have put it any better myself. This new "design" has AI slop written all over it. Especially those rounded corners ... yuck. The Firefox team has managed to vibe code the best browser around into a pile of slop (both performance and UI) in less than a year.  Incredibly sad.

[mh235]

The new tab design in Nova Design does not look good..

[ChuckTheNinja]

Came here to say exactly this. No one wants you to use dev resources on arbitrarily changing a design. If it is genuinely dated, people would complain about it. Change it then. There is no reason to change it before. I honestly hate the new tab groups icon and how you have, for some reason, decided that the window needed a color gradient instead of the flat dark grey that I specifically wanted.

[vy987]

I actively DISLIKE the rounded corners. They are harder to click and remind me of the slop other browsers are putting out there. Jesus Christ I've tolerated a lot of en**bleep**tification from Mozilla the past couple years, but if this isn't reverted or at least made optional to switch off soon I'll be moving to Waterfox. 

[Olov]

100% do not agree. I believe the look is great and feels modern. You don't want a browser stuck in 2002, right? And the browser works fine over here, updating the UI doesn't conflict with the browser being fast and easy to use. 

[jonblazeson]

It's terrible, sorry. Screen real estate is absolutely critical, and the previous theme was pretty close to spot on. Updating for the sake of updating is never, ever good. If ain't broke ... that phrase has stood the test of time. And right now, the FF UI is broken.

[vy987]

you are either in an echo chamber of devs who keep doing the opposite of what their users want, or just weird. 

[cadwellm]

As a person with rheumatoid arthritis, I wholly disagree with you. The NOVA tabs are shorter and the lack of corners means there is less area to click on. I find I'm clicking on 'air' and it takes more tries to get the tab I want.

So, your opinion that it looks great and feels modern doesn't help those in the disabled community that also have tactile difficulties.

We need the option to have larger and taller tabs...with corners...to make it easier on us.

But, of course, normies don't look at it from that side of things because they don't have to - because it doesn't affect them like it does others.

There should be an option for tab shape and size that is easy to change regardless of the UI for this reason alone!

[dftf]

Two things you could try:

1. URL bar -> about:config -> ENTER -> accept any warning -> search for nova ->
double-click on "browser.nova.enabled" to change the next column to "false".
That will undo the new UI

Or

2. Stick with the new UI, but increase the padding.  Right-click in an empty area on the toolbar or tab-bar, then click "Customise Toolbar".  At the bottom, change the "Density" to "Normal" or "Touch" (Touch being the most padded-out; Compact the least).

[cadwellm]

Thanks but I've already tried these things. The thing is I shouldn't have to. I have moved on to Waterfox and ESR.

[JNavas]

> And the browser works fine over here, updating the UI doesn't conflict with the browser being fast and easy to use. 

I guess I must be unlucky because with 157 I had to switch browsers to get some websites to work properly or to install sites as Progressive Web Apps.

Firefox has been my recent daily driver because it:

1. Still supports MV2 (important to me as an extension developer and user).
2. Has good support for extensions on Android (same as above).
3. Has good integration between Windows and Android.
4. Had decent support for most websites.
5. Had a decent UI without the silly changes afflicting other browsers.

Firefox nearly lost me when it sold out to Comcast on Private DNS, and now that #4 is eroding, #5 is gone, and Edge is starting to support extensions on Android, my remaining days on Firefox (even ESR) are probably numbered. It's a shame, because the Internet needs a successful Firefox.

Sic transit gloria mundi.

[kai452]

I had just changed back to firefox, after years when firefox came out with Quantum.
But with nova I wanted to escape again... until I found "browser.nova.enabled"...

Thank You so much ent1:
Every word is true for me, it's what I thought at the first glance on 157.
I'am on Linux because I want to be my own master, nobody has to told me what's right or not.
If one says, rounded corners are "modern" (they arn't (!), in former times we saw them already, it differs every x years from rounded to square and back again), it's just his OPINION.
If somebody has nothing else to do the whole day over, he will think about such bull**bleep** like "rounded" corners - HELP!!!

[dhja]

when you have full time developers as employees, you keep forcing updates to justify jobs. This forced nova upgrade smells exactly like a "job justification" based on a "Roadmap". I can see the layoffs coming soon.

[JNavas]

> when you have full time developers as employees, you keep forcing updates to justify jobs.

> This forced nova upgrade smells exactly like a "job justification" based on a "Roadmap". I can see the layoffs coming soon.

Mozilla actually has the opposite history: they’ve already suffered multiple massive rounds of layoffs over the last few years, losing a lot of key engineering talent in the process.

Unpopular UI overhauls rarely come from developers trying to pad their workload. Engineers usually hate unnecessary UI churn. Redesigns like this are top-down mandates from leadership and product management trying to prove market relevance on a shrinking budget, with predictable results.

[dhja]

there is a difference between what you identify as developers and what I mentioned. For engineers, leadership is engineering or product leadership. For companies, that is all development (R&D, IT, UX, or software). Someone somewhere is trying to justify their own or the software KPIs by making unnecessary cosmetic changes.

[JNavas]

> there is a difference between what you identify as developers and what I mentioned. For engineers, leadership is engineering or product leadership. 

I assure you that what I wrote is correct, based on my decades of experience running large software development organizations and knowledge of what happened at Mozilla.

[dhja]

very nice, it's great that you are providing a balanced response about this. Thank you

[Bhiu78]

It feels like Firefox has been getting constant updates lately, and honestly, the new design direction in version 157 is growing on me. I've always liked how customizable Firefox is compared to some of the other mainstream options, even if it takes a minute to get used to shifting UI elements around. Between testing out new browser updates, managing my open tabs, and dealing with everyday online admin—like sitting down to pay household bills and see detail monthly electricity statements before they pile up—my browser is always working overtime. Glad to see the team is keeping things fresh and performance running smoothly!

[roodypoo]

Did you use AI to write this? Are you kidding? Your use case is everyone else's use case while using a browser: opening mutiple tabs and...doing things onilne. This is a nothingburger glaze post and says and adds nothing of value. 

[JNavas]

Was that a paid promotional endorsement? 🙄

[MozillaUser1234]

This and a thousand time this.

[axol]

I don't like this rounded corner design. It looks very uncomfortable and awkward. I hope the square tab design can be changed back, or at least allow us to choose.

[dftf]

Web-address bar -> about:config -> ENTER -> search for nova -> double-click the line "browser.nova.enabled" -> "true" should change to "false"

UI should get reverted, until a future Firefox update removes that setting, or stops it working

[fo]

Thank you so much! I also turned off auto updates.

[dftf]

I wouldn't recommend turning-off the updates, as there could be a security issue then that you won't get patched for.

You'd be better off downloading the "ESR" version of Firefox from https://www.firefox.com/download/all/desktop-esr/ , uninstalling your current Firefox v157.0, restart your PC, then install the ESR version.  Then you'll still get security-fixes, but you won't get the new UI for around a year.

Might be worth backing-up your passwords, bookmarks and history before doing this, just in case: Menu > Settings > Account and Synchronisation > Turn on backup (unless you're already using it).  Then if your stuff is missing after you first start the ESR version, go back to that screen and use the "Restore your data" option to bring it back in