Examine source code of Shopee Item Blocker

{
  "manifest_version": 3,
  "name": "Shopee Item Blocker",
  "version": "1.1.0",
  "description": "Block specific Shopee listings. Blocked items are blurred with a click-to-peek button; everything is stored locally on your device.",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.shopee.com.my/*",
    "*://*.shopee.sg/*",
    "*://*.shopee.co.id/*",
    "*://*.shopee.co.th/*",
    "*://*.shopee.vn/*",
    "*://*.shopee.ph/*",
    "*://*.shopee.tw/*",
    "*://*.shopee.com.br/*",
    "*://*.shopee.cl/*",
    "*://*.shopee.com.co/*",
    "*://*.shopee.com.mx/*",
    "*://*.shopee.com.ar/*",
    "*://*.shopee.pl/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.shopee.com.my/*",
        "*://*.shopee.sg/*",
        "*://*.shopee.co.id/*",
        "*://*.shopee.co.th/*",
        "*://*.shopee.vn/*",
        "*://*.shopee.ph/*",
        "*://*.shopee.tw/*",
        "*://*.shopee.com.br/*",
        "*://*.shopee.cl/*",
        "*://*.shopee.com.co/*",
        "*://*.shopee.com.mx/*",
        "*://*.shopee.com.ar/*",
        "*://*.shopee.pl/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "Shopee Item Blocker",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "shopee-item-blocker@local.extension",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}