Examine source code of Mint Dark

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Dark Forest",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(30, 30, 30)",
      "toolbar_text": "rgb(253, 253, 253)",
      "frame": "rgb(23, 23, 23)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(29, 29, 29)",
      "toolbar_field_text": "rgb(226, 226, 226)",
      "tab_line": "rgb(57, 153, 126)",
      "popup": "rgb(223, 223, 223)",
      "popup_text": "rgb(32, 32, 32)",
      "tab_loading": "rgb(57, 153, 126)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f382bb5a-9051-4da2-a83b-0ba093c3d17d}"
    }
  }
}