Firefox 121 has a few changes designed to integrate better with desktop platforms.
On Windows, Firefox will now prompt you to install theMicrosoft AV1 Extensionto enable hardware decoding for AV1 video.
On Mac, Firefox now supports Voice Control commands.
The new version on Linux now uses theWayland compositorby default, instead of XWayland.
There’s also now a floating button to delete drawings, text, and images added in PDFs.
Source:Firefox Release Notes