Examine source code of Scroll Keeper

{
  "manifest_version": 2,
  "name": "Scroll Keeper",
  "version": "1.0",
  "description": "Save and restore scroll position on the current page.",
  "icons": {
    "48": "icons/icon_keep_48.png",
    "128": "icons/icon_keep_128.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon_keep_48.png",
      "128": "icons/icon_keep_128.png"
    }
  },
  "permissions": [
    "storage",
    "activeTab",
    "scripting",
    "<all_urls>"
  ],
  "applications": {
    "gecko": {
      "id": "scrollkeeper@luisfagundes.com"
    }
  }
}