Javascript Google Youtube嵌入式订阅按钮：未捕获类型错误：无法读取属性'；检查会话状态'；未定义的

当我试图在我的网站上嵌入YouTube订阅按钮时，我不断遇到这两个错误

Uncaught TypeError: Cannot read property 'checkSessionState' of undefined
    at callback (platform.js:75)
    at platform.js:32
    at tb (platform.js:24)
    at ba (platform.js:32)
    at Array.G.(anonymous function) (https://apis.google.com/js/platform.js:32:352)
    at Object.F.(anonymous function) [as loaded_1] (https://apis.google.com/js/platform.js:32:418)
    at cb=gapi.loaded_1:1

我使用的代码直接来自

显然，他们使用默认的数据通道来匿名。有什么想法吗？？提前谢谢

platform.js:75 Uncaught TypeError: Cannot read property 'checkSessionState' of undefined
    at callback (platform.js:75)
    at $b (platform.js:33)
    at ac (platform.js:31)
    at Z.Ce [as T] (platform.js:75)
    at Z.Y (platform.js:74)

<script src="https://apis.google.com/js/platform.js"></script>
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