Examine source code of TitleClipper

{
  "manifest_version": 2,
  "name": "Page Title Copier",
  "version": "1.0",
  "description": "Copies the current tab's title to clipboard.",
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png",
    "default_title": "Copy Page Title"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{24af9907-d7f2-4f0d-bfa3-e5e4b8257383}"
    }
  }
}