---
- name: Check for profiles.ini
  ansible.builtin.stat:
    path: "{{ ansible_env.HOME }}/.mozilla/firefox/profiles.ini"
  register: profile_ini
- name: Copy Firefox preferences to Profile0
  ansible.builtin.copy:
    src: user.js
    dest: "{{ ansible_env.HOME }}/.mozilla/firefox/{{ lookup('ini', 'Path section=Profile0 file={{ ansible_env.HOME }}/.mozilla/firefox/profiles.ini') }}/user.js"
  when: profile_ini.stat.exists