29-09-2026 06:30 AM - edited 29-09-2026 09:03 AM
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
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:
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.
02-10-2026 09:19 PM
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.
03-10-2026 09:29 AM
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.
03-10-2026 09:29 AM
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.
03-10-2026 09:32 AM
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.
03-10-2026 09:38 AM
you are either in an echo chamber of devs who keep doing the opposite of what their users want, or just weird.
29-09-2026 07:33 AM
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.
29-09-2026 10:56 AM
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
29-09-2026 01:06 PM
Thank you so much! I also turned off auto updates.
30-09-2026 12:53 AM
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
30-09-2026 04:22 AM
I wish they had two branches: one for their design crap and one for security and you can subscribe to either.
The way now you either get their design crap trojan horsed with security or you reject it all and go naked security wise.
30-09-2026 04:27 AM
Technically, they do: "beta" (one version ahead), "developer edition" (two versions ahead) and "nightly" (the most aggressively up-to-date) is where they test stuff.
Once they get feedback from those versions and something seems okay, it then makes it into the stable release. The ESR versions are for those who want change less-often.
30-09-2026 12:35 PM
Well, the dev and beta tester feedback is NOT WORKING. They just rolled out a UI update that made my browser trick me into believing I was having a nightmare where I was trapped in the new Barbie movie.
30-09-2026 12:10 PM
Well last couple of updates made FF much worse. It's unstable, slow, ugly. I use this browser for more than 20 years and I really struggle to remember when it was this bad. So no, I'm not worried about missing security updates. I'm more afraid that an update will make it even worse. Looks like AI has taken over the development... at least I hope it's the AI's fault.
I thank you for the info about config flag. That helped a little.
30-09-2026 12:38 PM
If AI did this, it was hallucinating.
Even the AI slop normally doesn't get this bad.
If actual people did this...well, same thing.
Don't do drugs, kids. Drugs are bad.
30-09-2026 06:03 PM
I don't care how bad the security fix is if they are gonna do this rounded stuff I'll just not update.
01-10-2026 07:57 AM
If they stopped making the user experience so much worse with every patch, maybe that would be an option.
At least I got back the ctrl+up/down keys for quick-switching search engines. Thank god.
01-10-2026 09:29 AM
'You'd be better off downloading the "ESR" version of Firefox "....OR....start using BRAVE as your default browser as this is making me ready to dl.
02-10-2026 02:20 AM
Don't recommend brave. It's got all kinds of even worse problems than Firefox. https://thelibre.news/no-really-dont-use-brave/
29-09-2026 03:49 PM
Thanks a lot! That was an eye-saver!
29-09-2026 07:52 PM - edited 29-09-2026 07:53 PM
Why should users hack their own browser, profiles, power users use more than one profile and hack each of them to make Firefox regular again? Such option must be in UI and change optional. not this. This is wrong.
30-09-2026 12:56 AM
I agree, but it's unlikely Firefox will revert the new UI so you have two choices:
1. Make the change I suggested in about:config
2. Download the latest 153.4.0 "ESR" release of Firefox, uninstall your current 157.0, restart your PC, then install the ESR version. Then you won't have the new UI for around a year from now, until you get moved to a newer ESR. Clearly that is more work though, and probably best to use the "Backup" option in Menu > Settings > Account and Synchronisation before removing 157.0 to ensure you don't lose anything in the move!
30-09-2026 06:43 PM
I would add a 3rd option to that list: switch to Vivaldi!
I did, and it is AWESOME. No more bubble tabs, no more psychedelic gradients, no more weird UI stuff...I set my appearance to rectangles only (no rounded corners at all), and straight black/white/gray color palette. It looks and functions exactly like a browser should - unobtrusive, invisible, just sitting there in the background serving up webpages like it's supposed to.
02-10-2026 10:31 AM - edited 02-10-2026 10:32 AM
Vivaldi is also the only major browser developed and owned in 🇪🇺 Europe too (🇳🇴 + 🇮🇸)
(🇺🇸: Brave; Chrome; Edge; Firefox; Safari. 🇳🇴 🇨🇳: Opera: HQ in Norway, but majority Chinese-owned)
01-10-2026 08:04 AM
I took the approach to disable updates. Its either that or finding a new browser. I don't trust the ff devs anymore, not when they push a UI that looks worse than a 3year old's doodles.
03-10-2026 09:40 AM
I am glad you posted your option but Firefox not having an easier way is unacceptable and we need to make that known at every opportunity. I do NOT want this browser to become slop run by devs who actively hate their customers.
30-09-2026 12:10 AM
Not all heroes wear capes my guy. I hope you stub your toe on a winning lottery ticket or a gold bar or something. Stay frosty mate ❤️
30-09-2026 12:29 AM
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.
30-09-2026 02:06 AM
You absolute legend. Actually looks a Firefox browser again after following your suggestion!
30-09-2026 07:12 AM - edited 30-09-2026 07:19 AM
Thaaaannnnnk !!!! from my eyes 😎
That was an undesired round update 😱 😩😡
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
30-09-2026 01:39 PM
fantastic. thank you
30-09-2026 02:27 PM
TY legend
30-09-2026 04:37 PM
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?
01-10-2026 12:10 AM
Complete and utter legend right here.
01-10-2026 07:32 PM
Nope. Didn't change to the old UI.
02-10-2026 02:14 AM
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
29-09-2026 10:35 PM
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.
30-09-2026 08:06 AM
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.
30-09-2026 06:47 PM
Try Vivaldi, for real - I switched and my browser looks like a browser again and it works great!
03-10-2026 09:43 AM
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.
29-09-2026 08:19 AM
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.