frp的subdomin不支持3级域名

[yujunchengg]

Describe the feature request

frp使用泛域名匹配模式代理http的时候，我域名是3级域名，比如a.b.baidu.com这种，我在frpc.ini的subdomin中设置为这个3级域名，启动直接失败

Describe alternatives you've considered

No response

Affected area

• [ ] Docs
• [ ] Installation
• [ ] Performance and Scalability
• [ ] Security
• [ ] User Experience
• [ ] Test and Release
• [ ] Developer Infrastructure
• [ ] Client Plugin
• [ ] Server Plugin
• [ ] Extensions
• [X] Others

[xqzr]

https://gofrp.org/docs/features/http-https/subdomain/

[github-actions[bot]]

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