Firefox 157 Ships the New Nova Design to Everyone

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Mozilla has started rolling out the new Firefox design to all users. The update ships with Firefox 157 on desktop and mobile and is the biggest visual refresh since the Proton redesign in 2021. Internally, Mozilla has been calling the work Project Nova.

The design was first announced in May, when Mozilla asked users to try it in Nightly and report what felt wrong. Four months later it ships as the default look.

Tabs, Colors, and Rounded Corners

The changes are easy to spot. Tabs, menus, the address bar, pop-overs, the sidebar, and search boxes are rounder than before, and all controls follow the same shape language instead of each looking slightly different. Mozilla describes the new palette as inspired by fire: a subtle glow around the active tab and warmer, smoky tones across the rest of the window. The icons have been redrawn and read better in both light and dark themes.

Desktop and mobile share the same foundations now, so the browser looks and behaves similarly on both. Mozilla also rebuilt the interface on reusable components and design tokens, which should keep future features from looking bolted on.

Compact Mode Returns

The most requested return: compact mode. It shrinks tabs and the toolbar so more of the screen goes to web content, which helps on small displays and in split-screen layouts. An auto option turns it on by itself when the window gets tight.

Themes, Wallpapers, Shortcuts

The theme picker has been reworked and comes with new themes and wallpapers. On the New Tab page there is now a dedicated area for pinning and organizing shortcuts, and the button for adding a custom shortcut is permanently visible instead of only showing on hover.

If the new look bothers you, it can be switched off for now: open about:config, look for browser.nova.enabled, and set it to false. No restart needed.

Settings and Privacy

The Settings redesign is meant to make data-related choices clearer. Privacy features like the built-in VPN and private browsing are easier to find, and there is a switch to turn AI features off completely.

On performance, Mozilla reports a 9 percent improvement in load times for key page content over the last year, plus quicker access to tab groups, split view, and vertical tabs.

Other Changes in Firefox 157