Examine source code of BrowsingDataCleaner

{
  "manifest_version": 2,
  "name": "BrowsingDataCleaner",
  "version": "1.2.0",
  "description": "Browsing Data Cleaner is a firefox extension to automatically delete browsing data such as cookie, sessionStorage, localStorage, cache, service worker, IndexedDB, plugin data, and form data. Deletions are performed on browser-startup, page-unload and shotcutkeys-pressed.",
  "icons": {
    "48": "icon48x48.png"
  },
  "permissions": [
    "cookies",
    "browsingData",
    "storage",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "initializeApp.js",
      "browserActionClickListener.js",
      "background/deleteBrowsingData.js",
      "background/onPageUnload.js",
      "background/onShortcutKeysPressed.js",
      "background/atBrowserStartup.js"
    ]
  },
  "content_scripts": [
    {
      "run_at": "document_start",
      "all_frames": true,
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content/onPageUnload.js",
        "content/onShortcutKeysPressed.js",
        "content/deleteBrowsingData.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "48": "icon48x48.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a5658d6d-a1ad-4555-a13b-fb84272ff4fc}"
    }
  }
}