Examine source code of vapourtrail

{
  "theme": {
    "images": {
      "theme_frame": "kondensstreifen9838a.jpg"
    },
    "colors": {
      "frame": "#1f25db",
      "tab_background_text": "#302d2d"
    }
  },
  "version": "2.0",
  "name": "vapourtrail",
  "manifest_version": 2,
  "description": "Kondensstreifen (vapour trails) / Dachsen (CH) / 24.3.2011, 19.55 h"
}