Video not supported (CORS + HTTP basic authentication) - no authentication prompt

Hello, 

since one of the last updates, we don't get our videos to play successfully. 
Interactive videos created before the update still work. 

We thought it's solved by setting up CORS correctly, but it's still not working.
Our videos are protected by a basic HTTP Authentication using .htaccess but the dialog for the authentication does not appear, causing a 401 (Authorization Required) in the browser console. 
It seems that the compatibility with the basic authentication is broken since the CORS update. 

https://h5p.org/node/569446

This is a sample video demonstrating the issue. 

It'd be great if you could look up into this issue. 

Thank you!

P.s: 
I've created a ticket here:
https://h5ptechnology.atlassian.net/projects/HFP/issues/HFP-2817

and also mentioned it here: 
https://github.com/h5p/h5p-moodle-plugin/issues/230#issuecomment-519938927