Can't use my custom modules out of the box (branch 17.0)

[Damien-VS]

context

encountered in 17.0
not tested on other branches

bug description

When building the hosted docker image

docker build -f "Dockerfile" -t dockerdoo:latest "."

The custom folder copy fails to do anything, executing with this command

#20 [production  8/13] COPY --chown=odoo:odoo ./custom /mnt/extra-addons

This is because the custom/* is in the .dockerignore file

expected

• I place a module in the ./custom directory
• I build & run the docker image through docker compose up -d
• the module is accessible in my odoo instance

fix proposal

• remove custom/* from .dockerignore
• explain why this behaviour is wanted in the README.md with a workaround / correct way to achieve the expected behaviour

🙏 Thanks