最终会员私人消息传递扩展不起作用

Question

当我尝试通过最终成员扩展名使用私人消息传递时，它不起作用。按钮消息显示Javascript:void(0);在浏览器的控制台中出现错误

这不是mCustomScrollBar: Uncaught TypeError: $(...).mCustomScrollBar is not a function on window resize

的重复问题

JQMIGRATE: Migrate is installed, version 1.4.1
um-messaging.min.js?ver=2.1.4:1 Uncaught TypeError: jQuery(...).css(...).mCustomScrollbar is not a function
    at Init_BodyConv (um-messaging.min.js?ver=2.1.4:1)
    at HTMLDocument.<anonymous> (um-messaging.min.js?ver=2.1.4:1)
    at i (jquery.js?ver=1.12.4-wp:2)
    at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4-wp:2)
    at Function.ready (jquery.js?ver=1.12.4-wp:2)
    at HTMLDocument.J (jquery.js?ver=1.12.4-wp:2)