: The built-in PDF viewer gained the ability to fill out more types of forms, including XFA-based forms used by many government agencies.
: Firefox 93 began blocking downloads that rely on insecure (HTTP) connections even if they were initiated from a secure (HTTPS) page, protecting users from "mixed content" vulnerabilities. Technical & Compatibility Notes Firefox 93.0 Free Download 2021
: This version added native support for the AV1 Image File Format (AVIF) , which offers significant bandwidth savings for websites compared to JPEG and WebP while maintaining high image quality. : The built-in PDF viewer gained the ability
: This update improved the "SmartBlock" mechanism that provides replacements for commonly blocked trackers, ensuring that websites don't "break" when tracking protection is set to Strict. Firefox 93.0 Free Download 2021