I was pretty sure to already have blogged about this ugly syntax: “pack://application:,,,” but apparently not.

This ugly syntax to get Uri referencing internal resources (Build action to Resource) is described here Pack URIs in WPF: “application:,,,” stands for “application:///” but ‘/’ must be replaced by ‘,’

Now it’s done.

It’s a good example of keep it simple and don’t try to take into account the entire world.