Why is app icon missing for toast notifications in action center on desktop?

Question

I'm developing an app that uses toast notifications to notify the user. These notifications are raised when the app is running in the background and go to the notification center.

All is well, but on desktop the app icon is missing for the notification group. When testing the app on Windows 10 Mobile the icon is there.

(Note: Shown above is the notification group for an app named "Calendar Activity", not the actual notification.)

Why is the app icon missing in the desktop's action center?

Here are some details about my assets:

I used the UWP Tile Generator to generate every asset you can configure in the app manifests 'Visual Assets' section. The files names look like this:

Toast notifications are generated using the UWP Community Toolkit classes, if that matters. So I'm not constructing the XML myself.

What am I missing? What is different between desktop and mobile regarding the notification group icons? Why is the notification icon missing on desktop?

(Win 10 Anniversary, SDK 10.0.14393.0, latest official update level for desktop and mobile (no Insider))

Answer 1

This is a know issue for desktop:

This is a known bug with the Anniversary Update (Version 1607). It only affects your app when deployed locally from Visual Studio. Your app will work correctly when deployed as a release package (like when installed from the Store). - Source