Examine source code of avatar-cookie-exporter

{
  "browser_action": {
    "browser_style": true,
    "default_title": "List cookies and localStorage in the active tab",
    "default_popup": "cookies.html",
    "default_icon": {
      "19": "icons/default19.png",
      "38": "icons/default38.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "halukapaydin@gmail.com_avatar-cookie-exporter",
      "strict_min_version": "87.0"
    }
  },
  "description": "List cookies in the active tab.",
  "icons": {
    "48": "icons/cookie.png",
    "96": "icons/cookie@2x.png"
  },
  "manifest_version": 2,
  "name": "avatar-cookie-exporter",
  "version": "1.3",
  "permissions": [
    "activeTab",
    "cookies",
    "<all_urls>",
    "tabs"
  ]
}