Note: On some devices I have to use a full path (file:///...) to the ASD (e.g. on a Nexus 5X, Android 8.1).
That shouldn’t actually be a problem. But the WebViewer component then requests READ permission. 
This permission is neither required nor do I want to allow it (I always remove storage permissions for my app from the Manifest). So I had to do it differently again and copied the two relevant files (duration.html and jquery-…min.js) into the PrivateDir and accessed them from there.
Fortunately, no permission is requested for this path (
PrivateDir).
