Google bug: "Oops, your web browser is no longer supported."

[Quotenfrau]

Hi

I use latest Firefbox with some security and privacy extensions and receive the error:

Oops, your web browser is no longer supported.

YouTube works with a wide range of browsers. However, if you'd like to use many of our latest and greatest features, please upgrade to a modern, fully supported browser.

Find the latest versions of our supported browsers below.

https://www.youtube.com/supported_browsers

others also? They wish to force me use Chrome?

 

[S.B.G]

Are you running a Flash blocker or NoScript?