GeoServer（Jetty/Java）配置Nginx反向代理后点击登录框出现非安全连接警告的求助

大家好，我最近碰到个棘手的问题，想请各位帮忙排查下：

我的环境是Debian服务器上部署的GeoServer v2.22.2，底层依赖Jetty/Java运行。先是按照教程配置了Nginx反向代理，之后用Certbot搞定了SSL证书，浏览器地址栏的安全锁显示是正常的。但当我点击登录界面的用户名/密码输入框时，会弹出非安全连接的警告，看起来像是混合内容问题，但我搞不清到底要调整Nginx的配置，还是GeoServer本身的设置。

下面是我当前的Nginx配置：

server {

server_name mydomain.com www.mydomain.com;

location / {

proxy_pass http://127.0.0.1:8080;

include proxy_params;

proxy_set_header X-Forwarded-Host $host:$server_port;

proxy_set_header X-Forwarded-Server $host;

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

proxy_set_header X-Forwarded-Proto $scheme;

}

listen [::]:443 ssl ipv6only=on; # managed by Certbot

listen 443 ssl; # managed by Certbot

ssl_certificate /etc/letsencrypt/live/mydomain.com/fullchain.pem; # managed by Certbot

ssl_certificate_key /etc/letsencrypt/live/mydomain.com/privkey.pem; # managed by Certbot

include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot

ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

add_header 'Content-Security-Policy' 'upgrade-insecure-requests';

}

server {

if ($host = mydomain.com) {

return 301 https://$host$request_uri;

} # managed by Certbot

listen 80;

listen [::]:80;

server_name mydomain.com www.mydomain.com;

return 404; # managed by Certbot

location / {

# root /path/to/myapp/public;

proxy_set_header X-Forwarded-Host $host:$server_port;

proxy_set_header X-Forwarded-Server $host;

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

proxy_pass http://172.0.0.1:8080;

}

add_header 'Content-Security-Policy' 'upgrade-insecure-requests';

}

我已经尝试在Nginx里加了upgrade-insecure-requests的内容安全策略头，但还是没解决这个问题。有没有朋友遇到过类似情况，或者能指出我配置里的问题，以及需要调整哪里呢？

备注：内容来源于stack exchange，提问作者phillip8