Works great! Top buttons change speed & pitch, bottom buttons change pitch by semitones (independent of speed). Well done!

Such a simple, incredible tool. The musical accuracy is very useful and so is the proportionality and lack of quality loss. Having great experience with it by giving new life to songs by the click of a button.

Fantastic addon for desktop version of Firefox.

Suggestions/ideas for the future:

[01] A 'Preserve Speed' slidebar option. Self-explanatory: pitch can be changed without affecting playspeed.

[02] Dedicated behavior modifier functions (additive, multiplicative) for play speed and pitch, separately.

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As of this posting date, this addon exhibits the following issue in Firefox Beta (Android):

[01] Within the menu interface, switching the On/Off slider to 'ON' position reverts back to 'OFF' position upon exiting, as well as forcing the active page to reload.

You can no longer change the settings or use commands

Does as good of a job with speed change as premium software. Thanks guy