提供一个自有gravatar头像源
https://gravatar.0sm.com/avatar/ #自有源
https://gravatar.loli.net/avatar/ #loli源
https://cdn.v2ex.com/gravatar/ #V2EX源
https://www.gravatar.com/avatar/ #Gravatar www源
https://secure.gravatar.com/avatar/ #Gravatar secure源
https://cn.gravatar.com/avatar/ #Gravatar cn源自建的反代的loli源 又拍云的CDN
下面是自有源效果
我用的helingqi