Hightlight.<name>.* not working with custom theme

[kkflt]

⚠️ Please verify that this bug has NOT been reported before.

• [x] I checked all existing issues and didn't find a similar issue

Description

title

👟 Reproduction steps

I have the following theme:

      extraPlugins = with pkgs.vimPlugins; {
        gruber-darker-nvim = {
          package = gruber-darker-nvim;
          setup = ''
            require("gruber-darker").setup {
              bold = true,
              invert = {
                signs = false,
                tabline = false,
                visual = false,
              },
              italic = {
                strings = false,
                comments = false,
                operators = false,
                folds = true,
              },
              undercurl = true,
              underline = true,
            }

            vim.cmd.colorscheme('gruber-darker')
          '';
        };
      };

And I also have

highlight = {
  Whitespace = { 
    fg = "#2c2c2c";
  };
};

However It doest work. A workaround I found is adding vim.api.nvim_set_hl(0, "Whitespace", { fg = "#2c2c2c" }) after the vim.cmd.colorscheme('gruber-darker') line and not using the highlight option

👀 Expected behavior

It wokr

😓 Actual Behavior

It dont workr

💻 Metadata

kkflt@tpad:~ nix-shell -p nix-info --run "nix-info -m" - system: "x86_64-linux" - host os: Linux 6.15.4, NixOS, 25.11 (Xantusia), 25.11.20250704.5c724ed - multi-user?: yes - sandbox: yes - version: nix-env (Nix) 2.28.4 - channels(root): "" - nixpkgs: /nix/store/cd7fkv2r1nflz758r8bsnqfvkq7f72wj-source

📝 Relevant log output

.