authelia: Remote error: tls: bad certificate with traefik v2 key + cert

I am using the keys generated by traefik v2 for authelia with a basic whoami example.

With traefik set up and working with https from the letsencrypt staging environment, I dump the cert and key files:

docker run -v /volumes/traefik/certs:/certs --rm ldez/traefik-certs-dumper file --version v2 --source /certs/acme.json --dest /certs/dump

This creates some cert files in /certs/dump. I copy both the key and crt files (wildcard ones) generated for authelia to use.

Authelia boots up, but when visiting whoami.mydomain.com I get a 500 and “Remote error: tls: bad certificate”.