Your ROOT_URL in app.ini is "https://gitea.ideaopen.cn/", it's unlikely matching the site you are visiting. Mismatched ROOT_URL config causes wrong URL links for web UI/mail content/webhook notification/OAuth2 sign-in.
This instance is configured to run under HTTPS (by ROOT_URL config), you are accessing by HTTP. Mismatched scheme might cause problems for sign-in/sign-up.

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