v13

I created odoo container from docker-compose fille. 

docker-compose.yml:

version: '3.7'
services:
  web:
    build: ./build
    depends_on:
      - mydb
    ports:
      - "18283:8069"
    environment:
      - HOST=mydb
      - USER=myuser
      - PASSWORD=mypassword
    restart: always
    #    volumes:
    # - ./config:/etc/odoo
    # - ./extra-addons:/mnt/extra-addons
    #    command: odoo -u mymodule
   mydb:
     image: postgres:12.1
     environment:
       - POSTGRES_DB=postgres
       - POSTGRES_PASSWORD=mypassword
       - POSTGRES_USER-myuser
     restart: always

inside build directory I have code from https://github.com/odoo/docker v13

Odoo works great, but I have problem with creating module.

I can't find them in Apps Odoo Search starting page. 

After docker-compose up

I typed: 

docker exec --user root -it <id_web_container> bash

> odoo scaffold <mymodule> /mnt/extra-addons/

I see in the /mnt/extra-addons/ directory that I have directory with <mymodule> name. It's Ok. 

I made it before create database in odoo and after this. Nothing changed.

I tried odoo -u <mymodule>.

I tried restart database and web containers and nothing helped. 

Any ideas?