Firefox 158 adds AI form filling and fixes 77 security flaws

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. What’s new in Firefox 158? Following the new Nova design introduced in Firefox 157, now a few technical boosts are being rolled out. The AI-based Smart Windows feature is designed to help users fill in forms more quickly. It’s being rolled out gradually, so it won’t be available to all users straight away. Another improvement involves the saving of web pages as PDFs. Firefox now generates more accessible PDF files (i. e. , fewer barriers), and a number of other shortcomings in PDF rendering have been fixed. Firefox now supports the JPEG XL image format, which has been