Docker and assets precompile problem with custom login page

Hello everyone
I am just testing Zammad with Docker for a project. I would like to customize login screen and also change some CSS to adopt the colors of my desire.
Everything works out of box except that I have struggled to make changes in the Coffescript files as well as Rails templates but changes do not reflect in the application and on login page.

I have tried to precompile the assets in the railsserver container but get error for Runtime environment not found.

Could you, anyone of you can guide ?

Thanks in advance.
/N

  • Used Zammad version:
    Zammad 6.2
  • Used Zammad installation type: (source, package, docker-compose, …)
    docker-compose
  • Operating system:
    MacOS
  • Browser + version:
    Google Chrome

Expected behavior:

Custom login page

Actual behavior:

Changes made in login.jst.eco do not reflect.

Steps to reproduce the behavior: