Examine source code of Grass Under Glass

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#5c1699",
      "tab_background_text": "#f0e9f2"
    }
  },
  "version": "2.0",
  "name": "Grass Under Glass",
  "manifest_version": 2,
  "description": "It is a picture of meadow grasses through a window."
}