Examine source code of Twitter Location

{
  "manifest_version": 2,
  "name": "Twitter Location",
  "description": "Shows country flags next to Twitter usernames",
  "version": "0.0.0",
  "icons": {
    "16": "/icon/icon-16.png",
    "32": "/icon/icon-32.png",
    "48": "/icon/icon-48.png",
    "96": "/icon/favicon-96x96.png",
    "128": "/icon/icon-128.png",
    "192": "/icon/web-app-manifest-192x192.png",
    "512": "/icon/web-app-manifest-512x512.png"
  },
  "permissions": [
    "storage",
    "tabs",
    "*://x.com/*",
    "*://twitter.com/*"
  ],
  "web_accessible_resources": [
    "page.js"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "versedev.store@proton.me",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Twitter Location",
    "default_popup": "popup.html"
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://twitter.com/*",
        "*://x.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/content.js"
      ]
    }
  ]
}