Xamarin.Forms UWP: Thumbnail buttons in Taskbar

I've developed a Xamarin.Forms application for Android and the UWP.

For the UWP part of my project, I want to add thumbnail buttons to the TaskbarButton, as like Skype.

I've searched around and only found websites from before 2015, so this information is outdated.
They even link to an SDK from which the link is dead. The subdomain doesn't even exist anymore.

https://archive.msdn.microsoft.com/WindowsAPICodePack

How can I achieve this in the UWP project of my Xamarin.Forms application?

Thanks in advance.