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Mozilla released Firefox 153.0 as the new Extended Support Release (ESR) for enterprises, schools, and other organizations seeking a long-term support browser baseline. The release adds initial Vulkan Video decode support, broadening hardware-accelerated playback beyond earlier Linux-focused VA-API work, and also brings HDR video playback on Windows systems with supported AMD and NVIDIA GPUs. Mozilla additionally highlighted PDF improvements and ongoing JPEG XL enablement, including experimental support carried forward from the beta cycle.
The update also includes security and privacy changes introduced during testing, including verification and display of Qualified Website Authentication Certificates (QWACs) in line with eIDAS requirements and a stricter default for browser extensions, which can no longer access local files unless users grant separate permission. Beta release notes also pointed to clearer location-permission indicators and a range of web-platform and developer updates, underscoring that Firefox 153 combines enterprise-focused stability with new media, document, and browser-hardening features.
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Mozilla began making Firefox 153 Extended Support Release available on the ESR channel for enterprise users on July 21, 2026. Mozilla highlighted enterprise-focused additions including profile management, Split View, profile backup and restore, centrally manageable on-device AI features, and expanded security protections.
Mozilla released Firefox 153.0 as its latest monthly browser update. The release became the newest Extended Support Release and added features including initial Vulkan Video decode support, along with PDF, JPEG-XL, and HDR video updates.
Mozilla first offered Firefox 153.0beta to Beta channel users on June 17, 2026. The beta release notes say this build included security and privacy changes such as QWAC display support and restricting extensions from accessing local files by default without separate user permission.
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Mozilla released **Firefox 152** for desktop and web platforms alongside **Firefox ESR 140.12.0** and **115.37.0**, delivering browser, developer, and mobile updates that include experimental **JPEG XL** support in Firefox Labs, changes to the Notifications and Pointer Lock APIs, `CSS field-sizing`, PDF handling improvements, and new Android features such as AI-assisted tab grouping and enhanced link-sharing options. The release also fixes **77 security vulnerabilities**, with Mozilla stating that **60** were memory-safety bugs and that some could potentially be exploited for **arbitrary code execution** when processing specially crafted content. The patched issues include groups tracked as **`CVE-2026-12328`**, **`CVE-2026-12327`**, and **`CVE-2026-12326`**, making the update a significant security release for both standard and ESR Firefox users.
Jul 12, 2026
Mozilla released **Firefox 155** and maintenance updates for Firefox ESR 153.2.0, 140.15.0, and 115.40.0. The release remediates **109 security vulnerabilities**, including memory-safety issues that malicious websites could potentially exploit for arbitrary code execution or other browser compromise; organizations should prioritize deployment across managed Firefox installations. Firefox 155 also introduces an experimental AI-assisted “Smart Window” feature for a limited user set, alongside web-platform, developer-tool, PDF viewer, Android, HTTP/3, WebAssembly, CSS, JSON, WebTransport, and Windows controller updates. Several experimental platform capabilities remain disabled by default and can be enabled through `about:config`; the release also changes captive-portal detection from `detectportal.firefox.com` to `firefox-portal-detection.com`.
Sep 5, 2026
Mozilla released **Firefox 157** with fixes for 76 vulnerabilities, including 38 rated high severity. The high-severity issues include memory-safety flaws that could allow attacker-controlled code execution if a user opens a specially crafted web page; Mozilla reported no vulnerabilities rated critical and the available advisories do not identify active exploitation. Mozilla also issued security updates for **Firefox ESR 153.4.0, 140.17.0, and 115.42.0**. Users and administrators running earlier Firefox or ESR versions should upgrade promptly. Firefox 157 additionally introduces the experimental Nova sidebar interface, enables AV1 screen sharing support in WebRTC, and includes CSS and JavaScript dialog improvements.
Oct 2, 2026