Skype Preview support

[BAndonovski]

Is your feature request related to a problem? Please describe.
If a user enables the new preview version of Skype, notifications no longer work and the unread message badge no longer appears.

Describe the solution you'd like
I'd like the notification and unread message badge to work :)

Describe alternatives you've considered
For now, not turning on the preview version. But that will not be possible soon enough.

Additional context
Nope.

[closingin]

Hello,

The problem is that "trying out" the new version redirects you to preview.web.skype.com, it's not just about setting a cookie to enable it. So I don't think we're going to create a service or just to serve a beta version of Skype as it's surely not that stable, and fixing the current one wouldn't be the way to go.

We just have to wait until this goes live in production.

@adlk -> won't fix ?