Examine source code of fox w/ gradient

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#ff9500",
      "tab_background_text": "#15ff00"
    }
  },
  "version": "2.0",
  "name": "fox w/ gradient",
  "manifest_version": 2,
  "description": "A simple outline with a gradient inside the fox and one in the background"
}