Examine source code of Willow

{
  "theme": {
    "images": {
      "theme_frame": "willow-1.jpg"
    },
    "colors": {
      "frame": "#2e0a0a",
      "tab_background_text": "#9e8c67"
    }
  },
  "version": "2.0",
  "name": "Willow",
  "manifest_version": 2,
  "description": "Our fraidy-cat Willow"
}