Examine source code of black cat sleep

{
  "name": "black cat sleep",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Xmass gold(19).jpg"
    },
    "colors": {
      "frame": "rgba(0, 0, 0, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(0, 0, 0, 0.14)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(0, 0, 0, 0)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e6c0a0fb-4b33-45b8-8f1a-f9f0bd7b782f}"
    }
  }
}