Unfree packages throw an error when installing to user profile

[iopq]

Expected:

When you click install it installs it to your user profile, fixing any errors

Actual:

error:
       … in the condition of the assert statement

         at /nix/store/k5l01g2zwhysjyl5zjvg5zxnj0lyxpp1-source/lib/customisation.nix:268:17:

          267|     in commonAttrs // {
          268|       drvPath = assert condition; drv.drvPath;
             |                 ^
          269|       outPath = assert condition; drv.outPath;

       … while evaluating the attribute 'handled'

         at /nix/store/k5l01g2zwhysjyl5zjvg5zxnj0lyxpp1-source/pkgs/stdenv/generic/check-meta.nix:490:7:

          489|       # or, alternatively, just output a warning message.
          490|       handled =
             |       ^
          491|         (

       (stack trace truncated; use '--show-trace' to show the full trace)

       error: Package ‘roomeqwizard-5.30.9’ in /nix/store/k5l01g2zwhysjyl5zjvg5zxnj0lyxpp1-source/pkgs/applications/audio/roomeqwizard/default.nix:112 has an unfree license (‘unfree’), refusing to evaluate.

       a) To temporarily allow unfree packages, you can use an environment variable
          for a single invocation of the nix tools.

            $ export NIXPKGS_ALLOW_UNFREE=1

          Note: When using `nix shell`, `nix build`, `nix develop`, etc with a flake,
                then pass `--impure` in order to allow use of environment variables.

       b) For `nixos-rebuild` you can set
         { nixpkgs.config.allowUnfree = true; }
       in configuration.nix to override this.

       Alternatively you can configure a predicate to allow specific packages:
         { nixpkgs.config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [
             "roomeqwizard-5.30.9"
           ];
         }

       c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
         { allowUnfree = true; }
       to ~/.config/nixpkgs/config.nix.