PCWorld reports that Mozilla has released Firefox 158, introducing an AI-powered Smart Windows feature for automatic form filling and adding support for the efficient JPEG XL image format. The update patches 77 security flaws, including 30 high-risk vulnerabilities, with 24 capable of allowing malicious code execution and eight potentially enabling attackers to escape the browser sandbox. Users are advised to update Firefox immediately to close these dangerous security gaps. Firefox 158 is out for Windows, macOS, Linux, and Android. This version brings improved PDF support, the ability to fill forms with the help of "AI," as well as fixes for over 75 security vulnerabilities. Updates are also available for Firefox ESR versions. Firefox 159's release is scheduled for October 27th, 2026.