Examine source code of Beautiful Jellyfish

{
  "theme": {
    "images": {
      "theme_frame": "jellyfish_firefox_header.jpg"
    },
    "colors": {
      "frame": "#616161",
      "tab_background_text": "#c7c7c7"
    }
  },
  "version": "2.0",
  "name": "Beautiful Jellyfish",
  "manifest_version": 2,
  "description": "Purple Jellyfish on a black baggrund"
}