A utility function for userscripts that detects and handles AJAXed content.
此脚本不应直接安装。它是供其他脚本使用的外部库，要使用该库请加入元指令 // @require https://update.cn-greasyfork.org/scripts/446257/1059316/waitForKeyElements%20utility%20function.js
A utility function for userscripts that detects and handles AJAXed content.
For use as a require header.
