Examine source code of DevHeader

{
  "manifest_version" : 3 ,
  "name" : "__MSG_appName__" ,
  "version" : "0.1.0",
  "description" : "__MSG_appDescription__" ,
  "default_locale" : "en" ,
  "permissions" : [
    "declarativeNetRequest" ,
    "declarativeNetRequestWithHostAccess" ,
    "storage" 
  ],
  "host_permissions" : [
    "<all_urls>" 
  ],
  "background" : {
    "scripts" : [
      "lib/i18n.js" ,
      "lib/storage.js" ,
      "lib/dnr-builder.js" ,
      "background/service-worker.js" 
    ]
  },
  "action" : {
    "default_popup" : "popup/popup.html",
    "default_title" : "DevHeader",
    "default_icon" : {
      "16" : "icons/16.png",
      "48" : "icons/48.png",
      "128" : "icons/128.png"
    }
  },
  "icons" : {
    "16" : "icons/16.png",
    "48" : "icons/48.png",
    "128" : "icons/128.png"
  },
  "options_ui" : {
    "page": "welcome/welcome.html" ,
    "open_in_tab": true
  },
  "commands" : {
    "_execute_action": {
      "suggested_key": {
        "default": "Alt+Shift+D"
      }
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "devheader@local.dev",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}