Firefox 121 is out with AV1 improvements, new features for PDF viewer, and more December 19, 2023 by admin Tweet Mozilla has released Firefox 121 in the Release channel. The final feature update in 2023 brings improvements for AV1 video decoding, new features for the PDF viewer, and other changes. Read more… Neowin Related Posts:Firefox 124 is out with Windows jumplist…Firefox 109 is out with Manifest V3 extensions…Mozilla launches Firefox 100 with lots of video…Microsoft updates Edge Dev with new actions in Adobe…Firefox 110 is out with improved data import, GPU…