Examine source code of Daily Random Fact

{
  "manifest_version": 2,
  "name": "Daily Random Fact",
  "version": "1.0",
  "description": "Discover a new random fact every day.",
  "permissions": [],
  "browser_action": {
    "default_icon": "icons/fact-48.png",
    "default_popup": "popup.html",
    "default_title": "Random Fact"
  },
  "icons": {
    "48": "icons/fact-48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d3032a03-0954-4e99-8943-d35fe7b3aa25}"
    }
  }
}