In continuation to my first post -
WPF Popups and ToolTip behavior - A Journey
I decided to approach the implementation of such a popup like the ToolTip and ContextMenu are doing it themselves.
I did not inherit from Popup but rather created my own control and I used the Popup.CreateRootPopup which sets the Popup.Child property to my control and it picks up on all the ToolTipService properties defined on my control.
I started from reading the following post:
Popup your control
There were some problems with this pattern though, I had to overcome these with quite many event hooking which I'm not very happy about. At least it works for now :)
There is a way to improve the implementation, I could use mouse capturing but that introduced another set of problems so I left it as it is for the time being.
I will post my solution soon enough.
CodeProject