Can't run flectra 2.0 in a docker

[AntonSchmied]

When following the steps described here
https://hub.docker.com/r/flectrahq/flectra

I want to test flectra 2.0 thus altering to
docker run -p 7073:7073 --name flectra --link db:db -t flectrahq/flectra:2.0

However, when I try to run the application in a browser under localhost:7073 I get
Internal Server Error

EDIT:
please update the documentation, as flectra 2.0 seems to work when postgres version is set to "15"
docker run -d -e POSTGRES_USER=flectra -e POSTGRES_PASSWORD=flectra -e POSTGRES_DB=postgres --name db postgres:15