Examine source code of Messenger Emotes (7TV)

{
  "manifest_version": 3,
  "name": "Messenger Emotes (7TV)",
  "version": "1.1.0",
  "description": "7TV emotes for Facebook Messenger with autocomplete",
  "browser_specific_settings": {
    "gecko": {
      "id": "messenger-emotes-7tv@example.com",
      "strict_min_version": "112.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://www.facebook.com/*",
    "https://facebook.com/*",
    "https://7tv.io/*",
    "https://cdn.7tv.app/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.facebook.com/*",
        "https://facebook.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup.html"
  }
}