For some reason, for example only one splashscreen size is supported (620x300). When I add other sizes by adding the following line:
<splash src="../resources/themes/windows-phone/img/splashscreen/splashscreen.scale-140.png" width="868" height="420" />
The image isn't copied to the cordova/platforms/windows/images folder when building. This is the reason why it's also not included and referenced in the resulting package.windows.appxmanifest.
Why is that?? Or am I doing something wrong?