Compatibility with apt-transport-tor

Hello and please tell me if this isn't the right place to ask this question.

It seems apt-cacher-ng doesn't work well with apt-transport-tor. If in acng.conf I put:

Remap-debrep: file:debian_mirrors ; tor+http://vwakviie2ienjx6t.onion/debian/

It will crash with this error:

tor+http://vwakviie2ienjx6t.onion/debian/ <-- bad URL detected

Can anything be done so apt-cacher-ng will allow packages to be fetched through Tor and cache them as well ?

Thank you.