Examine source code of loopa

{
  "manifest_version": 2,
  "name": "loopa",
  "version": "1.0",
  "description": "Loop sections of videos slowly",
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Loopa",
    "default_popup": "popup/index.html"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e12b42c5-3bd0-450c-814c-2958580746e8}"
    }
  }
}