Examine source code of Paint with Firefox

{
  "theme": {
    "images": {
      "theme_frame": "firefox.PNG"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Paint with Firefox",
  "manifest_version": 2,
  "description": "Not sure if this is going to work (custom persona acted weird, but you can use any image for that, so I'm crossing fingers this will work). On top it is supposed to say \"I Love Firefox!\" and on the bottom \"Yay Mozilla!\", all made using Paint. "
}