Examine source code of Chatfossil

{
  "manifest_version": 3,
  "name": "Chatfossil",
  "version": "1.0.0",
  "description": "Keeps a copy of your WhatsApp Web messages on your device and searches them — text, media, files and links.",
  "homepage_url": "https://chatfossil.com",
  "icons": {
    "16": "assets/icon-16.png",
    "32": "assets/icon-32.png",
    "48": "assets/icon-48.png",
    "128": "assets/icon-128.png"
  },
  "action": {
    "default_title": "Open Chatfossil",
    "default_icon": {
      "16": "assets/icon-16.png",
      "32": "assets/icon-32.png",
      "48": "assets/icon-48.png",
      "128": "assets/icon-128.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "host_permissions": [
    "https://api.fxtwitter.com/*",
    "https://api.vxtwitter.com/*",
    "https://pbs.twimg.com/*",
    "https://video.twimg.com/*"
  ],
  "optional_host_permissions": [
    "https://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://web.whatsapp.com/*"
      ],
      "js": [
        "vendor/wppconnect-wa.js"
      ],
      "world": "MAIN",
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://web.whatsapp.com/*"
      ],
      "js": [
        "bridge.js"
      ],
      "world": "ISOLATED",
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://web.whatsapp.com/*"
      ],
      "js": [
        "archive-db.js",
        "archive-sync.js",
        "search-ui.js",
        "launcher.js"
      ],
      "world": "MAIN",
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "chatfossil@chatfossil.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  }
}