How to detect speech-to-text support and what is the meaning of mozSpeechRecognition, msSpeechRecognition, oSpeechRecognition? - webspeech-api

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John Rizzo wants to draw more attention to this question:
I'm convinced that there is someone experienced in Webspeech API who knows, or who has better internet-search skills than I, and could bring a clear answer.
I'm trying to better understand when Webspeech speech-to-text is actually avaialable and operational.
In this process I see these few lines code all over the web, for assessing is speech-to-text is supported by the browser:
const NativeSpeechRecognition = typeof window !== 'undefined' && (
window.SpeechRecognition ||
window.webkitSpeechRecognition ||
window.mozSpeechRecognition ||
window.msSpeechRecognition ||
window.oSpeechRecognition
)
According https://caniuse.com/speech-recognition all actually supporting browsers (chrome, Opera, UC, Samsung, Safari, QQ, Baidu) use the webkit prefix: window.webkitSpeechRecognition.
The caniuse.com table says that speech-to-text does not work on Edge (109 incl), while on my Windows PC, it works with Edge 109.0.1518.78., for my own JS web app (using the react-speech-recognition package and also with https://dictation.io/speech).
My web searches on "oSpeechRecognition" or "mozSpeechRecognition" or "msSpeechRecognition" have not been instructive.
I've run that code sandbox to know which of these is defined.
var recognition = new (window.SpeechRecognition ||
window.webkitSpeechRecognition ||
window.mozSpeechRecognition ||
window.msSpeechRecognition)();
recognition.lang = "en-US";
recognition.interimResults = false;
recognition.maxAlternatives = 5;
recognition.start();
console.log("window.SpeechRecognition", window.SpeechRecognition);
console.log("window.webkitSpeechRecognition", window.webkitSpeechRecognition);
console.log("window.mozSpeechRecognition", window.mozSpeechRecognition);
console.log("window.msSpeechRecognition", window.msSpeechRecognition);
console.log("selected recognition", recognition);
recognition.onresult = function (event) {
console.log("You said: ", event.results[0][0].transcript);
};
On Chrome 109, the console is:
window.SpeechRecognition undefined
window.webkitSpeechRecognition ƒ SpeechRecognition() {}
window.mozSpeechRecognition undefined
window.msSpeechRecognition undefined
selected recognition EventTarget {grammars: Object, lang: "en-US", continuous: false, interimResults: false, maxAlternatives: 5…}
On Edge 109, the console is exactly the same:
window.SpeechRecognition undefined
window.webkitSpeechRecognition ƒ SpeechRecognition() {}
window.mozSpeechRecognition undefined
window.msSpeechRecognition undefined
selected recognition EventTarget {grammars: Object, lang: "en-US", continuous: false, interimResults: false, maxAlternatives: 5…}
On Firefox 109, the sandbox does not run.
TypeError undefined is not a constructor $csb$eval /src/index.js:1:18
var recognition = new (window.SpeechRecognition ||
I'd like to understand:
Why caniuse.com says speech-to-text does not work on Edge?
Why I can't even make the code run on Firefox?
What is the origin/purpose of mozSpeechRecognition, msSpeechRecognition, and oSpeechRecognition that is copied on many code examples and articles with no comment and no explanation. As if it is some 10 years old historical code that no one understands, is not useful anymore but everyone uses.
Many thanks.
John.