Examine source code of Site Blocker Extension

{
  "manifest_version": 2,
  "name": "Site Blocker",
  "version": "1.2",
  "description": "Block websites by domain. Add domains to block and manage them from the popup.",
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_title": "Site Blocker",
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png",
      "128": "iconx128.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "site-blocker@kyox.com",
      "data_collection_permissions": {
        "required": [
          "locationInfo"
        ],
        "optional": [
          "technicalAndInteraction"
        ]
      }
    }
  }
}