Mozilla Firefox 99.0: here is what is new

Mozilla released Firefox 99.0 Stable, Firefox 91.8.0 ESR and Firefox 99.0 for Android on April 5, 2022 to the public. The new release includes security fixes, sandbox strengthening on Linux devices, and support for autofill and capture of credit card data in Germany and France.

All development channels are also updated. Firefox Beta and Developer editions are upgraded to version 100.0, and Firefox Nightly is moved to 101.

Executive Summary

  • Firefox 99.0 and Firefox 91.8 ESR include security fixes.
  • Firefox’s Linux sandbox has been improved in this release.

Firefox 99.0 download and update

Here are the links to the official download repositories.

Firefox 99.0 new features and improvements

Firefox on Linux includes an improved sandbox. The change limits the access of processes that are exposed to web content so that they no longer have access to the X Window system (X11).

Other changes

  • Credit Card autofill and capture is supported in Germany and France in the new release.
  • The keyboard shortcut n toggles the Narrate feature in Reader Mode.
  • Search support with and without diacritics in the PDF Viewer.

Developer Changes

  • navigator.pdfViewerEnabled is now enabled, and is the recommended way to determine whether a browser supports inline display of PDF files when navigating to them
  • Firefox supports the RTCPeerConnection.setConfiguration() method now.
  • The Network Information API is disabled by default on all platform because it “it exposes a significant amount of user information that might be used for fingerprinting”.

Enterprise changes

  • An issue with Outlook Web Access was resolved that caused some fields to work improperly.
  • Fixed the ability to install add-ons from if install_sources in ExtensionSettings specified a different source.

Known Issues

Gallery Mode in the Zoom web client is accessible in Firefox, but video may not work always with “breakout rooms in gallery mode”. The issue may be resolved by leaving the room and re-entering it.

Security updates / fixes

Security updates are revealed after the official release of the web browser. You find the information published here after release.


Firefox 99 is the last major two-digit release of the browser. The next release is Firefox 100, which will be out on May 3, 2022 according to the schedule. There is the chance that some site functionality may break, for instance, when sites parse the user-agent string of Firefox incorrectly. System administrators may use the network.http.useragent.forceVersion preference to keep the version in the user agent below 100.

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Mozilla Firefox 99.0: here is what is new

Article Name

Mozilla Firefox 99.0: here is what is new


Mozilla released Firefox 99.0 Stable, Firefox 91.8.0 ESR and Firefox 99.0 for Android on April 5, 2022 to the public.


Martin Brinkmann


Gacks Technology News



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