Examine source code of Stempeluhr Upgrade

{
  "manifest_version": 2,
  "name": "Stempeluhr Upgrade",
  "version": "0.1",
  "description": "Verbesserung der Stempeluhr.",
  "permissions": [
    "storage",
    "https://agenda-stempeluhr/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://agenda-stempeluhr/gfos*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "gfos-extension@agenda.local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}