Examine source code of unInsta

{
  "manifest_version": 3,
  "name": "unInsta",
  "description": "Unsend all your messages in an Instagram DM conversation",
  "version": "0.1.99",
  "permissions": [],
  "action": {
    "default_icon": {
      "16": "icons/icon16-gray.png",
      "32": "icons/icon32-gray.png",
      "48": "icons/icon48-gray.png",
      "128": "icons/icon128-gray.png"
    },
    "default_title": "unInsta - Toggle panel"
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png",
    "256": "icons/icon256.png",
    "512": "icons/icon512.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.instagram.com/direct/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle",
      "world": "MAIN"
    },
    {
      "matches": [
        "https://www.instagram.com/direct/*"
      ],
      "js": [
        "bridge.js"
      ],
      "run_at": "document_idle",
      "world": "ISOLATED"
    }
  ],
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "uninsta@dustfeather",
      "strict_min_version": "149.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}