The guid globally unique identifier is a 128 - bit unique identification string used to identify a class or an interface Guid （全局唯一标识符）是用于标识类或接口的128位唯一标识符字符串。
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Specifies the length of the browser identification string to use as the key for caching browser capabilities objects in the internal cache 指定浏览器标识字符串的长度，该标识字符串要用作内部缓存中的缓存浏览器功能对象的键。
