Examine source code of checkered firefox

{
  "theme": {
    "images": {
      "theme_frame": "greyfoxheader.jpg"
    },
    "colors": {
      "frame": "#fa7908",
      "tab_background_text": "#fcfcfc"
    }
  },
  "version": "2.0",
  "name": "checkered firefox",
  "manifest_version": 2,
  "description": "Classic firefox logo with grey and black checkered background."
}