JSFiddle - React, Tailwind, and code Playground

HTML

<button id="play_pause">Play/Pause</button><br><br>
<video id="player" controls autoplay width="320" height="240"></video>

JavaScript

var player = document.getElementById('player');
var playPause = document.getElementById('play_pause');

var stream, myMediaRecorder;

navigator.mediaDevices.getUserMedia({video: true}).then(function (streamHandle) {
    player.srcObject = streamHandle;
    stream = streamHandle;
    myMediaRecorder = new MediaRecorder(streamHandle);
    myMediaRecorder.start();
});

playPause.onclick = function () {
    if (player.paused) {
       player.play();
       myMediaRecorder.resume();
    } else {
       myMediaRecorder.pause();
       player.pause();
    }
};