JS Hook (Coursera Playback Speed)

hook.js

//webpack:///./static/bundles/video-experimental/constants.js
//webpack:///./static/bundles/video-experimental/components/settingsMenu/VideoSettingsMenu.jsx

const speeds = [];
const playbackDelta = 0.250001;
for (let i = 0.75; i <= 10; i += playbackDelta)
	speeds.push(i);



let hooked = false;
const old = Array.prototype.findIndex;

function findIndex() {
	if (!hooked) {
		const error = new Error();
		if (/VideoSettingsMenu/.test(error.stack) && this.length == 6 && this[0] == 0.75 &&
				this[1] == 1 &&
				this[2] == 1.25 &&
				this[3] == 1.5 &&
				this[4] == 1.75 &&
				this[5] == 2) {
			
			Array.prototype.splice.apply(this, [0, this.length].concat(speeds));
			//undo hook
			hooked = true;
			Array.prototype.findIndex = old;
		}
	}
	return old.apply(this, arguments);
}

Array.prototype.findIndex = findIndex;