Update the favicon of the page to display the number of unread notifications

Idea from nlemoine:

"Update the favicon of the page to display the number of unread notifications" - just like GMAIL does for example.

From Nicolas:

IIRC, it is possible to have a dynamical favicon, Google uses it to display the number of unread emails in the inbox.

Could it be possible to view the unread or new notifications in the browser favicon for the XWiki notifications? It's important that it refreshes quite often to avoid inaccurate info.