async requre element
This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://update.greasyfork.org/scripts/448197/1512335/ElementGetter20.js
async requre element
异步获取元素的脚本库，解决元素延迟加载的问题，相比定时器实时性好，还有性能强
source https://bbs.tampermonkey.net.cn/thread-2726-1-1.html