The isFinal read-only property of the SpeechRecognitionResult interface is a boolean value that states whether this result is final (true) or not (false) — if so, then this is the final time this result will be returned; if not, then this result is an interim result, and may be updated later on.
A boolean value.
recognition.onresult = (event) => {
const color = event.results[0][0].transcript;
diagnostic.textContent = `Result received: ${color}.`;
bg.style.backgroundColor = color;
console.log(event.results[0].isFinal);
};