Firefox 99 Available With Strengthened Linux Sandbox, Web MIDI

Written by Michael Larabel in Mozilla on 5 April 2022 at 06:34 AM EDT. 63 Comments
Mozilla is officially shipping Firefox 99 today and the last feature release before next month's Firefox 100 milestone.

Firefox 99 is a modest release with several changes this month worth noting for this cross-platform, open-source web browser.

Firefox 99's Linux sandbox has been strengthened so the processes exposed to web content no longer have access to any underlying X11 server. Firefox 99 did enable GTK overlay scrollbar support during nightly and early beta releases as another Linux-specific improvement but that functionality is disabled for the stable release.

Firefox 99 also introduces the Web MIDI API for offering some level of web integration around MIDI protocol devices such as synthesizers, musical keyboards, and other controllers. Web MIDI offers a simple JavaScript API for interfacing with MIDI devices. Web MIDI has already been supported by Google Chrome.

Other changes with Firefox 99 include PDF viewer search support with/without diacritics, toggling the narrate in reader mode functionality via the "n" keyboard shortcut, and user-agent string testing around compatibility with next month's Firefox 100 (three digit version) release.

That about wraps up the notable changes of Firefox 99. Ahead of Mozilla's official announcement, Firefox 99.0 can be downloaded from the server.
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