Origin file:// produce 403 Forbidden from REST API

Hi,

I need help for the following problem. If I start the app with the command 'ionic run --device -l' everything ist ok.
I can see that ionic set in request header of REST -API the Origin : localhost:8100.
But if I start the app without liveload with command 'ionic run --device' the Origin would set to file://
My API backend allows every origin, with an IP or an hostname but not file://, here I get the code 403 Forbidden.

So why is cordova set the origin to file://? How I can solve the problem?