I'm pleased to announce complete MP3 audio support for TenFourFox, i.e., HTML5 audio using MP3 (with minimp3 as the decoder since 10.4 AudioToolbox lacks MP3 decoding) -- the last remaining piece was getting intratrack seeking to function and I finished that up over the weekend. So far I've tested it against Soundcloud, Amazon Music and a few other sites as well as my own audio library and it all seems to work properly. Seeking is sequential, so it's a little slow on long tracks, but playback functions pretty much as expected. MP3 support will still ship disabled in 38.4.0 but if all goes well it will be publicly rolled out in 38.5.0 as I previously promised. The QTE will of course still work for playing tracks outside of the browser.

(*apologies to TMBG, "Dinner Bell" from Apollo 18)

http://tenfourfox.blogspot.com/2015/10/waiting-for-mp3-to-do-tune-thing-mp3.html