Examine source code of Dark Brushes

{
  "name": "Dark Brushes",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "abstrakt24.png"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(16, 93, 110, 0.66)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(109, 24, 133, 0.6)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a1b84e30-868c-4c2e-8f1d-9399ae6d1c97}"
    }
  }
}