Examine source code of Credit Card Generator: Test Card Numbers

{
  "manifest_version" : 3 ,
  "name" : "__MSG_appName__" ,
  "short_name" : "CC Generator",
  "version" : "1.0.1",
  "default_locale" : "en" ,
  "description" : "__MSG_appDesc__" ,
  "homepage_url" : "https://ccgenerator.org/",
  "browser_specific_settings": {
    "gecko": {
      "id": "ccgenerator@ccgenerator.org",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "icons" : {
    "16" : "icons/icon16.png",
    "32" : "icons/icon32.png",
    "48" : "icons/icon48.png",
    "96" : "icons/icon96.png",
    "128" : "icons/icon128.png"
  },
  "action" : {
    "default_popup" : "popup.html",
    "default_title" : "__MSG_appName__" ,
    "default_icon" : {
      "16" : "icons/icon16.png",
      "32" : "icons/icon32.png",
      "48" : "icons/icon48.png",
      "128" : "icons/icon128.png"
    }
  },
  "background" : {
    "scripts" : [
      "src/cards.js" ,
      "background.js" 
    ]
  },
  "options_ui" : {
    "page": "options.html" ,
    "open_in_tab": true
  },
  "permissions" : [
    "storage" ,
    "menus" ,
    "activeTab" ,
    "scripting" 
  ],
  "optional_permissions" : [
    "clipboardRead" 
  ],
  "commands" : {
    "_execute_action": {
      "suggested_key": {
        "default": "Alt+Shift+C"
      }
    },
    "fill-test-card": {
      "suggested_key": {
        "default": "Alt+Shift+F"
      },
      "description" : "__MSG_cmdFillDesc__" 
    }
  }
}