About a year ago, I had curiosity how to develop Google Chrome extension. Once you play next video, then previous video stopped automatically, that's what I wanted to implement. Like Facebook videos, but I wanted to use Youtube videos on the page.

I will insert un-related videos here among the sentence. Then, you can test my extension from here.

The extension

You can download from here. I didn't publish. I only wanted to implement, that's all. So, this link will help you how to apply on your browser with this. Clone the repo,  turn developer mode on and use Load Unpacked button in chrome://extensions/.

Try it!

Now you can play first video, play next video during playing first one. It's simple implementation. That's all.