Branding.InjectResponsiveCSS is not working when applied to mysite

office 365 PnP has a solution for adding responsiveness:

https://github.com/SharePoint/PnP/tree/master/Samples/Branding.InjectResponsiveCSS

Howesver, when i run the solution, it did not work.

When i went to mobile view of the chrome, it did not change the menu did not change.

The demo tells about the menu changing to ham burger while we are in the process of shortening the size.

However, in mobile view it does not get applied.

Why so?

Thanks,

Naba