Firefox Browser, also known as Mozilla Firefox or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko layout engine to render web pages, which implements current and anticipated web standards. In 2017, Firefox began incorporating new technology under the code name Quantum to promote parallelism and a more intuitive user interface. Firefox is officially available for Windows 7 or newer, macOS, and Linux. Its unofficial ports are available for various Unix and Unix-like operating systems including FreeBSD, OpenBSD, NetBSD, illumos, and Solaris Unix.
What's new in 157.0.1
Version 157.0.1, first offered to Release channel users on October 6, 2026
Fixed
Fixed downloads failing on macOS when Firefox is set to ask where to save files but doesn't have permission to access the Downloads folder. (Bug 2077390)
Fixed the sidebar getting stuck on the Bookmarks or AI Chatbot panel for some users. (Bug 2076296)
Fixed the Restore from Backup option not appearing during onboarding on Windows. (Bug 2073401)
