Examine source code of Black Cracks

{
  "name": "Black Cracks",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "abstrakt26.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(82, 11, 70, 0.66)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(74, 1, 34, 0.71)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(213, 0, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{40bca46e-f3b9-4419-9553-abba3ed4310e}"
    }
  }
}