Cannot get allowUnfree to work with home-manager module

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1

I have tried to follow multiple guides and dotfiles to make sure the pkgs are configured correctly for nix-darwin to allow paid packages. However updating the system by running nix run command still throws warning about adding allowUnfree attribute.

I have enabled useGlobalPkgs = true in home-manager. And I have configured nixpkgs.config for nix-darwin as well.

Here is my flake. nix-config/flake.nix at 30219dcb867de29a6ea60ba6c888d765d6dbf1fb · maulik13/nix-config · GitHub

I get the error about unfree package for a firefox addon at nix-config/programs/firefox.nix at 30219dcb867de29a6ea60ba6c888d765d6dbf1fb · maulik13/nix-config · GitHub

Any help here would be great. Many thanks!

2 
darwin.lib.darwinSystem {
  # ...
  modules = [
    home-manager.darwinModules.home-manager
    { nixpkgs.config = config; } # This is missing.
    # ...
  ];
}
3

I tried adding that like this in my code but it did not work. I also have useGlobalPkgs = true in my home-manager config so I assume it should pick up the nixpkgs config from nix-darwin.

  darwin.lib.darwinSystem {
    inherit pkgs;
    inherit system;
    modules = [
      home-manager.darwinModules.home-manager
      (
        home-manager-user {
          user = host.user;
          path = ./systems/${host.dir}/home.nix;
        }
        // {
          nixpkgs.config = config;
        }
      )
    ]
  }
4

I realized that the issue is caused by a firefox addon which comes from nur repository. I found a thread here that gave me a solution to this. After adding an overlay like this (copied from other thread), it worked fine.

# flake.nix
  inputs = {
    nur.url = "github:nix-community/nur";
  };
# home.nix
{ inputs, ... }:
{
  nixpkgs = {
    overlays = [
      inputs.nur.overlay
    ];
    config = {
      allowUnfree = true;
    };
  };
}
# firefox.nix
{ pkgs, ... }:
{
  programs.firefox = {
    enable = true;
    profiles = {
      default = {
        extensions = with pkgs.nur.repos.rycee.firefox-addons; [
          enhancer-for-youtube # non-free
        ];
    };
  };
}