Firefox’s biggest redesign in years just landed with Nova

Firefox 157 is out for Windows, macOS, Linux, and Android and the biggest change in this version is the new Nova design, which brings a more modern look to the browser. Mozilla has also fixed over 70 security vulnerabilities, and updates are also available for the Firefox ESR versions.

The release of Firefox 158 is scheduled for October 13th, 2026.

What’s new in Firefox 157?

Now that Firefox has adopted a two-week release cycle, major new features are growing fewer and farther between. With Firefox 157, the focus is on the new Nova design, which has heavily rounded corners and subtle color gradients on surfaces. You’ll find 12 themes, each in light and dark variants.

Mozilla has also brought back the popular Compact Mode, which groups elements together to save space—great for smaller screens.

You can learn more about the Nova redesign and what it entails in this announcement post by the Mozilla team.

Security fixes in Firefox 157

In the security advisory for Firefox 157, Mozilla lists 76 vulnerabilities that have been fixed, 30 of which were discovered and reported by external security researchers.