Examine source code of A Rustic Rainbow

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#f2e6e6",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "A Rustic Rainbow",
  "manifest_version": 2,
  "description": "A spin on the classic rainbow pattern with rustic shades. Subdued yet colourful and easy on the eyes."
}