Mozilla Adds AI Chat to Firefox 155, Fixes 29 Security Flaws

Mozilla Foundation is expanding Firefox’s role beyond conventional web browsing by testing Smart Window, an AI chat feature designed for interaction within the browser. The move places Mozilla in the industry-wide contest to make generative AI a core browsing interface, while raising the stakes around privacy and user control. Firefox 155 also strengthens visibility into online tracking and gives users more flexibility in organizing isolated browsing environments.

Firefox 155 makes Smart Window available on a trial basis in selected countries, with broader availability not yet specified. The release adds a tracker count display and a sorting mechanism for containers, helping users monitor tracking activity and manage separated browsing sessions. Mozilla also addressed 29 security vulnerabilities in the update, including several dangerous flaws assessed as critical by the U.S. Cybersecurity and Infrastructure Security Agency, or CISA.