Require this script and you will get variable GMRequireChecker equals to true if loaded. In other cases, variable GMRequireChecker will just not exists.
Este script não deve ser instalado diretamente. É uma biblioteca destinada a ser incluída por outros scripts através da diretiva de metadados // @require https://update.greasyfork.org/scripts/429557/951692/GMRequireChecker.js
A simple script to check whether @require works.
if it works, then you can get variable GMRequiredJSLoaded which equals to true. Otherwise, GMRequiredJSLoaded will just not exist.
You can also use this script to check whether your script is running in a non-ScriptManager-environment.