PCWorld notes that Firefox 157 introduces the Nova redesign, the browser's biggest visual overhaul in years, featuring rounded corners, subtle color gradients, and 12 unique themes with light and dark modes. A new Compact Mode helps users save screen space, making Firefox more practical for smaller displays. Mozilla also released ESR security updates fixing dozens of vulnerabilities, with older system support continuing until March 2027. 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.