Examine source code of Shortcut Enhancer

{
  "manifest_version": 2,
  "name": "Shortcut Enhancer",
  "version": "1.0",
  "description": "A simple add-on to save and use custom shortcuts for websites.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{da3c1fa7-0e66-4654-96cd-89b2b102f50d}"
    }
  }
}