BlazerYoo

Option 1: Command-line download extension as zip and extract

extension_id=jifpbeccnghkjeaalbbjmodiffmgedin   # change this ID
curl -L -o "$extension_id.zip" "https://clients2.google.com/service/update2/crx?response=redirect&os=mac&arch=x86-64&nacl_arch=x86-64&prod=chromecrx&prodchannel=stable&prodversion=44.0.2403.130&x=id%3D$extension_id%26uc" 
unzip -d "$extension_id-source" "$extension_id.zip"

Thx to crxviewer for the magic download URL.

UPDATED 3.12.2020

The old version of youtube with "disable_polymer" is not working anymore, so the script also stopped working.

Thanks to JanTheDeveloper we have a new working script. Big up!

I just changed the '//span[contains(text(),"Watch later")]', to '//span[contains(text(),"Remove from")]', and it should work for any playlist, not just the watch later one. (thanks to hudsonite for the tip)

setInterval(function () {
 document.querySelector('#primary button[aria-label="Action menu"]').click();

	const express = require('express');
	const path = require('path');

	const app = express();
	const port = 3000;

	app.use(express.static(path.join(__dirname + '/files')));

	app.get('/', (req, res) => {
	res.sendFile(path.join(__dirname + '/files/index.html'));

	import os
	for f in os.listdir():
	if f.endswith('.PNG'):
	os.rename(f,os.path.splitext(f)[0]+'.png')

	@echo off
	echo %*