Examine source code of japan-red

{
  "name": "japan-red",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "firefox-01.jpg"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(255, 255, 255, 1)",
      "bookmark_text": "rgba(107, 0, 0, 1)",
      "toolbar_field": "rgba(148, 0, 0, 1)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(0, 0, 0, 0.31)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f76e9271-bfa8-4736-8eab-86cbe30c23e0}"
    }
  }
}