failure to load an ontology

[jonassmedegaard]

This ontology fails to load at the playground site, with this error:

The request body was invalid.

It succeeds at WebVOWL.

[jonassmedegaard]

Hm, it loads when bypassing the content negotiation, i.e. adding extension .ttl.

Am I doing something wrong (the ontology is my making, and I am hosting it myself as static files with handwritten Apache2 config) and WebVOWL is overly forgiving, or is this perhaps a bug of failing to handle content negotiation?