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.
01-10-2026 12:29 AM
Address bar -> about:config -> ENTER -> accept warning -> search nova -> double-click line "browser.nova.enabled" -> "true" changes to "false"
Change should get mostly undone
30-09-2026 06:56 PM
I have submitted an idea to better distinguish regular and Private windows. Please consider.
01-10-2026 05:19 AM
Idea Not Found
The idea you are trying to access is not available.
Return to my original page
? 🤔
30-09-2026 07:43 PM
Please give the users you supposedly care about. The option to toggle back to the old UI design.
Many of us find the previous layout much more intuitive and user-friendly plus it looked nicer no like some generic slop you cooked up in less than a minute with the help of AI.
Providing a legacy layout option would show that you truly listen to us your community.
01-10-2026 12:20 AM
To toggle back to the old UI:
Type about:config in the address-bar, then press ENTER
Accept any warning
Search for nova
Double-click the line "browser.nova.enabled" to set the value to "false"
30-09-2026 07:51 PM - edited 30-09-2026 07:52 PM
I made an account just so I can add some feedback: I can't delete my browser history by just right clicking a group of websites anymore. I must either delete each website individually, or Firefox forces me to go through the entire Clear Browsing Data pop-up menu which is incredibly counter intuitive and unnecesary.
30-09-2026 08:54 PM - edited 01-10-2026 02:50 AM
Why has the minimum sidebar width increased, I keep the bookmarks sidebar open all the time as small as possible to give me more usable space, this is weird when you've bought back compact mode to do the same then I lose space widthways.
Edit: Remove sidebar as before with about:config Sidebar.revamp. =false
30-09-2026 09:12 PM
The new 157.0 update is extremely slow, YouTube is basically unusable. The CPU usage is moving between 100% - 49%. This update Suck. Please figure out what's happening and fix it. This is so bad I'm surprised this thing got released.
01-10-2026 12:19 AM
I'm using 157.0 with the uBlock Origin extension and am having no issues
So for people who are, you likely use another extension that is causing an issue
First go to Menu > Extensions and Themes > click the ⚙ icon > Check for Updates
If any get updated, fully-close all Firefox windows, bring a new one up, and see if it's fixed
If not, in Menu > Extension and Themes click "Extensions" and try disabling one
Close all Firefox windows, then bring a new one back up
Repeat until you've found the extension causing the issue
01-10-2026 03:54 AM
Seems to be the "Ghostery extensio". I de activated it and the CPU usage went down.
30-09-2026 09:39 PM
I'm tired of these big UI elements and super round corners and round icons and elements, and wasted empty space and toyish-mobile like things all over. I'm so done. I'm switching to Vivaldi or something else. Please back to the old radius and design overall. even apple did setback with liquid glass and all the stupid floanting and super round things (even though i didnt fix the mess they made). please mozilla, dont.
30-09-2026 11:32 PM
Yeah! After the the liquid glass received lots of feedback apple gave users option to change the transparency of their new UI, on this Nova design lots of users already asked for OPTIONS to change the roundness etc but they still pushed through on making the design default on stable
30-09-2026 10:14 PM
I hate it. That's the most honest I can be about it without direct hostility to your teams. I hate it. It is awful, it doesn't deserve to exist. It has done nothing but irritate. What a godawful design choice. What a godawful team to have signed off on the design choice.
30-09-2026 10:29 PM
That’s why I use it—it’s still beautiful, with a futuristic design. However, the tab area is smaller than before...
30-09-2026 10:35 PM
Oh, I used this to fix it, and the tabs have become large again.-browser.nova.enabled-
30-09-2026 10:44 PM
I turned it off as first thing to happen this morning, that's kinda telling. Bad desing imo.
30-09-2026 10:50 PM - edited 30-09-2026 10:50 PM
was this "Mozilla Connect community" blind?
30-09-2026 11:13 PM - edited 30-09-2026 11:15 PM
I find the new design quite gross tbh and it sucks I can't change it without making some kind of change I don't really want to do. If I wanted to use a trash browser, I'd have stuck with Edge. If anything, at the VERY LEAST, give us an option to switch between two styles. Rounded tabs just suck because they waste space and it looks like I'm reading thru a port hole.../cringe. Tires are round, tabs are square. I'm sad you guys paid people to do this.
Edit: For the first time, since you were born from Netscape Navigator, have I thought to change browsers.
01-10-2026 12:14 AM
If you've not done so already, switch back by following these steps:
In the web-address bar, type about:config then press ENTER
Accept any warning
In the search-box, type nova
Double-click the line "browser.nova.enabled" to change it from "true" to "false"
01-10-2026 12:15 AM
I use Firefox at work. The new design looks unprofessional and distracting. Please at least add an option to revert to the old design, instead of forcing this child cryon painting theme on us.
01-10-2026 12:18 AM - edited 01-10-2026 12:18 AM
Same here I refuse to use edge or chrome, at first I tried if I'll get used to the new design but I folded a day after by turning off nova on about:config
01-10-2026 12:54 AM
Address bar -> about:config -> ENTER -> accept warning -> search nova -> double-click the line "browser.nova.enabled" -> should say "false" after. That will undo most of the new changes.
You may also wish to recommending your IT team there move to the "ESR" release of Firefox (https://www.firefox.com/download/all/desktop-esr/), as that gets security fixes and bug fixes, but no UI changes and rarely any new features between major updates, which are around a year apart
01-10-2026 12:48 AM
It's nice, but you can no longer quickly switch between bookmarks and history when the bookmarks sidebar is open. You used to be able to do this quickly using a small arrow—a feature I used ALL the time. That option is still there if you open the history first and want to switch to bookmarks.
01-10-2026 12:52 AM
This is a known-bug in the 157.0 release, yes
To fix it right now, follow these steps:
The down-arrow should then return
01-10-2026 03:40 AM
Restore old sidebar setup about:config sidebar.revamp. =false
01-10-2026 02:25 AM
It's disgusting. Make it stop.
01-10-2026 02:28 AM
To stop it right now:
Type about:config in the web-address bar, then press ENTER
Accept any warning, if shown
Type nova in the search-box on the next screen
Find the row with "browser.nova.enabled" in it, and double-click it so it says "false" after
That should undo most of the changes
01-10-2026 02:34 AM
Thanks for offering one place to let our voices be heard.
Apparently, I am not the only one who is not happy with the rounded tabs (and more). Sometimes, we just have to get used to something new; sometimes, the "new" is so obtrusive we that have to go look for alternatives... I LOVE Firefox and I don't want to look for alternatives, but if Firefox decides to take away the option to revert from Firefox 157 back to it's wonderful 156 look (with square tabs), I'm afraid I'll have to look further.
In other words: please please please do not remove the about:config option to restore the Firefox 156 look (search for browser.nova.enabled, and set it to false).
Many thanks!
01-10-2026 02:49 AM
for non native english speakers, your YT is hard to understand, try articulating more, please
01-10-2026 03:06 AM
They appear to have disabled YouTube's auto-dub feature on the video, too.
You can change the subtitle language to your own one though, if that helps. Use the ⚙ icon that appears at the top of the video when you hover over it
01-10-2026 02:59 AM - edited 01-10-2026 03:18 AM
My first step after loading up FireFox after this update was to immediately look up how to disable this new UI change. It was quite a visceral feeling.
I am reminded of a story about the New Coke debacle from years ago. I am not sure how accurate it is, it may have well been one of those urban myth things that has stuck with me for awhile. But the gist of it was that Coke got a set of stats that showed more people preferred the taste of Pepsi. So, they tried to make their Coke taste more like Pepsi. The problem was that the interpretation of that stats like that meant that they ruined their flavor for the smaller portion of people who absolutely loved it and then didn't really draw in people who liked Pepsi since they like Pepsi. I am afraid that this is the same kind of avenue that is being approached here and it is not going to go well. Chasing UI decisions because other people may like that kind of UI in other browsers does not mean that the people who like your browser already are going to like those UI decisions.
More constructively, if you are going to be pushing UI updates, you need to make sure that you are checking the boxes for accessibility at the very least. Messing with element sizes, functionalities, and color schemes can mess with accessibility for persons with issues like color-blindness, a sensitivity to the high contrast, a dependency on very high contrast, persons who may have issues with interacting with controls due to size, and so on. I don't like the new layout, but even if I did, I am very doubtful that the necessary accessibility considerations were taken. It doesn't alleviate that to have more themes, since an user that has accessibility requirements is still going to have difficulty navigating now to implement a new theme.
Additionally, I am very tired of getting the feature highlights all the time. It seems the only use of those anymore is to have an idea of the vernacular I need to search for in order to disable some new 'feature'. I get more excited anymore when I open of Firefox and don't see a "What's New" page, or a random pop-up that says Firefox can now do X, Y, or Z. It has been so long since any of it seemed applicable to anything I use Firefox for that I just close out of it instantly without hardly a glance.
I love Firefox and continue to do so, but this direction lately ain't it chief. I do not like my tabs looking like pills. I do not like the shading effect. I do not like that it affects the color palette for highlighted items when I went to change the item in the about:config page. I resent that I had to go to about:config to revert this, and more resentful that this communication seems to indicate that Firefox is leaning towards removing the about:config option to revert it in the future.
Before this, I was definitely a Firefox person. Now I am not sure. I'm not lost as an user yet, but if you are bent on this direction as a company I don't know how much longer I am going to be interested in using Firefox.
03-10-2026 10:08 AM
@anotherBob wrote:Additionally, I am very tired of getting the feature highlights all the time. It seems the only use of those anymore is to have an idea of the vernacular I need to search for in order to disable some new 'feature'. I get more excited anymore when I open of Firefox and don't see a "What's New" page, or a random pop-up that says Firefox can now do X, Y, or Z. It has been so long since any of it seemed applicable to anything I use Firefox for that I just close out of it instantly without hardly a glance.
**bleep**, this exactly. With every one of the last few updates, the "What's new" page popping up causes more and more dread in me, and then at best functions as an outline to find out what I need to change/look up/break. It's so tiring. Software didn't use to be this mentally exhausting to deal with.
@anotherBob wrote:I resent that I had to go to about:config to revert this, and more resentful that this communication seems to indicate that Firefox is leaning towards removing the about:config option to revert it in the future.
Before this, I was definitely a Firefox person. Now I am not sure. I'm not lost as an user yet, but if you are bent on this direction as a company I don't know how much longer I am going to be interested in using Firefox.
This, too. "Resent" is exactly the word. I've just spent, like, an hour out of my Saturday - after being flashbanged by an ugly, inaccessible, reduced-functionality UI update - looking up how to reverse the update (thanks, dftf), then creating a whole new account for this forum, and adding kudos to posts and replies. All to hopefully make this feedback clearer and not have this clearly worse-at-being-UI design permanently forced on to my browser in the future.
It's - again - so tiring.
01-10-2026 03:49 AM
The combination of Multi-Account Containers and Vertical Tabs was probably not tested I'm guessing? It looks so bad it's downright unusable.
01-10-2026 05:23 AM
the top bar is so small now i can barely read it this is horrible that this is forced
01-10-2026 05:29 AM
It's only forced to the extend they don't provide an easy way in the settings to turn it off
Go into the hidden-settings (type about:config in the URL bar, then press ENTER) and search for nova then double-click "browser.nova.enabled" to set it to "false". That'll undo most of it
01-10-2026 05:25 AM
Ugly, horrible design. Having gradients on everything looks cheap and ugly. The round corners are a horrible plague on society and have ruined plenty of other applications and websites. Presenting an alternative skin with obviously more squared options only for it to still be the ugly circles is a slap in the face.
Why does Mozilla hate it's users so much? Why do you keep making these terrible changes no one asked for? Your data collection model is horrible because, like any sane person should, I have mine disabled and you will never collect my usage data. Take time to actually ask your community instead of relying on the anonymous data collected from the idiots who don't read anything and just leave all of their options set to default.
01-10-2026 05:28 AM
If you haven't already, you can undo many of the new UI changes by going to about:config (type that in the address-bar, then hit ENTER), then search for nova and set "browser.nova.enabled" to "false"
01-10-2026 06:19 AM
I have, thanks to you in other comments.
01-10-2026 05:40 AM
The way I wish people would "fixing" things that are NOT broken. There was ZERO reason to change icons and the way things look such as application menu. Now it's smaller and harder to see! YOU SHOULD HAVE LEFT IT ALONE. wth.
01-10-2026 05:47 AM
If by "application menu" you mean the main Firefox menu (when you tap the three-lines icon) you can likely increase this by right-clicking a blank area of the toolbar -> Customise toolbar... -> change "Density" at the bottom to something like "Normal" or "Touch"