Youtube video plays on only one single tab in firefox

I am using Firefox as a browser, I have Ubuntu 18.04. The main problem is that I can't play two or more youtube videos in different tabs. In fact, once I play the video in the second tab, the first one pauses automatically.

1 Answer

Thanks @Xen2050, the problem was due to the extension called "Youtube enhancer", it did not allow me to play two or more youtube videos simultaneously on different tabs.