SpeechSynthesis.getVoices() not listing voices in Firefox

[Abhishek Potnis]

I am developing an application that requires me to use text to speech in
the web browser. I am using the HTML5 Speech Synthesis for it. On Google
Chrome the code runs fine, with all the available voices being listed using
|getVoices()|, but in Firefox no voice is listed at all. I am testing my
code on Firefox 56.0 (Ubuntu).

On searching over the internet, I did come across a StackOverflow answer
<https://stackoverflow.com/questions/21513706/getting-the-list-of-voices-in-speechsynthesis-of-chrome-web-speech-api>
that
suggested that the getVoices() function should be called after the
|onVoiceChanged| event

window.speechSynthesis.onvoiceschanged = function() {
window.speechSynthesis.getVoices();
... };

I am invoking the call in the above mentioned manner and it works as
desired in Chrome, but not on Firefox.

Another StackOverflow answer suggested that I enable the
|media.webspeech.synth.enabled| in about:config of Firefox, but in my
Firefox the preference |media.webspeech.synth.enabled| is already set to
true.

I checked the MDN documentation
https://developer.mozilla.org/en-US/docs/Web/API/SpeechSynthesis/getVoices and
the example on this page does not run for me in Firefox, but runs fine in
Chrome. I found that CanIUse.com
<http://caniuse.com/#feat=speech-synthesis> lists
that SpeechSynthesis as supported in Firefox 55 onwards, but it does not
work for me.

Also The demo <http://mdn.github.io/web-speech-api/speak-easy-synthesis/> by
Mozilla Developer Network to demonstrate the Speech Synthesis fails to work
on my Firefox, but runs fine on Google Chrome. I have extensively searched
online for a solution but could not find one. Can someone please point me
in the right direction here.

--
Regards,
Abhishek V. Potnis
Ph.D. Student,
Centre of Studies in Resources Engineering,
Indian Institute of Technology Bombay.
http://home.iitb.ac.in/~abhishekvpotnis

[jrmath...@gmail.com]

Hi, did you ever find a solution to this? I have the same issue, but under Windows 10. The speechSynthesis.getVoices() call returns an empty array.