Firefox

Mozilla ships Firefox 151 on May 19, 2026, patching 25 security vulnerabilities and adding PDF merging, Document PiP, Web Serial API, and tighter fingerprinting controls.

Mozilla released Firefox 150 on April 21, 2026, fixing 271 vulnerabilities surfaced by Anthropic's Claude Mythos Preview in a security sweep Mozilla's CTO calls a turning point for defender-side AI.

Firefox 149 routes browser traffic through a proxy network to mask IP addresses, offering 50 GB of free monthly data in four countries with no extension required.

Mozilla releases Firefox 149 with a complimentary browser-only VPN, side-by-side tab browsing, and automatic permission revocation for malicious sites.

Mozilla delivers on its kill switch promise: Firefox 148 adds a single toggle to block all current and future AI features, arriving February 24.