Quote:The first three-digit version of Mozilla's Firefox web browser has been released on May 3, 2022. Firefox 100 introduces a whole range of new features and improvements, including captions and subtitle support on YouTube for Picture-in-Picture, multiple language spell checking, HDR video on Mac, and hardware accelerated AV1 video decoding on Windows.



Firefox 91.9.0 ESR and Firefox 100 for Android are also released. All development channels have seen a version bump as well. Firefox Beta and Developer editions 101, and Firefox Nightly 102 are now also available.

Executive Summary

• Firefox 100 is the first version on Windows that is signed with SHA-256. On Windows 7 devices, KB4474419 is required to install Firefox successfully.
  
• Some sites or services may break, if they use incorrect parsing of the user-agent. Chromium reached 100 as well recently, and this issue applies to all browsers that reach this version. Mozilla has support pages for desktop and Android for users who run into compatibility issues.
  
• Firefox 102 is the next ESR release.
  

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