Examine source code of Typography Unlocker

{
  "manifest_version" : 3 ,
  "name" : "Typography Unlocker",
  "version" : "2.0",
  "description" : "Detect, preview, inspect, and extract web fonts from any website instantly.",
  "permissions" : [
    "downloads" ,
    "activeTab" ,
    "scripting" ,
    "storage" ,
    "contextMenus" 
  ],
  "host_permissions" : [
    "<all_urls>" 
  ],
  "icons" : {
    "16" : "icons/icon16.png",
    "32" : "icons/icon32.png",
    "48" : "icons/icon48.png",
    "128" : "icons/icon128.png"
  },
  "action" : {
    "default_popup" : "popup.html",
    "default_title" : "Typography Unlocker",
    "default_icon" : {
      "16" : "icons/icon16.png",
      "32" : "icons/icon32.png",
      "48" : "icons/icon48.png",
      "128" : "icons/icon128.png"
    }
  },
  "options_page" : "options.html" ,
  "content_scripts" : [
    {
      "matches" : [
        "<all_urls>" 
      ],
      "js" : [
        "content.js" 
      ],
      "run_at" : "document_idle" 
    }
  ],
  "background" : {
    "scripts" : [
      "background.js" 
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "typography-unlocker@personal-use.local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}