I installed this specifically for Spotify playback. For some reason, Spotify doesn't support speed control, even for podcasts, on their website. Once you install this addon, you will have to "reload" the Spotify site, then it works! The controls are simple and easy to use, and you can adjust the speed while something is playing. Haven't tried it with other sites yet, but the other site I use the most (YouTube) already supports playback speed control.

Me gustaria que al pasar de x4 el audio no se perdiera.
No tenia ni idea, gracias

ممتاز شكرا

I really love this addon. If support Android Firefox browser，That will great!

It was greatly working on youtube and another regional portal i'm use to visit, but lately it stopped to work on both websites. It's a great tool, thank you developer!

I use the same extension in Chrome as well. It supports Youtube Videos.

For Spotify Web, you need to install this add-on as well: https://addons.mozilla.org/en-US/firefox/addon/spotify-csp-clear/ The developer is working on improving this GlobalSpeed plugin so that it won't need Spotify CSP Clear in the future.

I'm using this plugin to help practice the bass guitar during covid quarantine - slowing down the songs/videos to help me to learn the song.