Seafile-WebDav behind Nginx proxy (Docker)

Hello,
I need help configuring Seafile-WebDav behind a reverse proxy (nginx). I’ve read all the topics regarding this subject on the forum but can’t find a solution.
Nginx as well as Seafile are running in as separate docker containters. The seafile webpage, seafile client as well as seadrive client work without any issue. I just can’t get webdav working. If I try to connect the following error occurs:

seafdav.access.log:
79.XXX.XX.XXX 192.168.64.2 [10/Feb/2021:22:16:23 +0100] "PROPFIND /seafdav/ HTTP/1.1" 499 0 "-" "Strongbox/3026 CFNetwork/1220.1 Darwin/20.3.0" -

Additionally the client (used to connect to seafile) comes up with a message “Connection timed out”.

I have no idea what causes this behavior. It would be very nice if someone could give me a hint what I’m doing wrong. Thank you!

This is my seafdav.conf:

[WEBDAV]
enabled = true
port = 8080
fastcgi = false
share_name = /seafdav

This is my nginx template for seafile:

server {
    listen        80;
    server_name   _;
    server_tokens off;

    location /seafile {
      rewrite ^ https://$http_host$request_uri? permanent;    # force redirect http to https
    }
}

server {
    listen        443 ssl http2;
    server_name   _;
    server_tokens off;

    ssl_protocols TLSv1.2;
    ssl_certificate /etc/ssl/private/cacert.pem;
    ssl_certificate_key /etc/ssl/private/privkey.pem;
    ssl_dhparam /etc/ssl/private/dhparam2048.pem;
    ssl_ecdh_curve secp384r1;
    ssl_ciphers EECDH+AESGCM:EDH+AESGCM:EECDH:EDH:!MD5:!RC4:!LOW:!MEDIUM:!CAMELLIA:!ECDSA:!DES:!DSS:!3DES:!NULL;
    ssl_prefer_server_ciphers on;
    ssl_session_timeout 10m;

    location /seafile {
        proxy_pass         http://127.0.0.1:8000;
        proxy_set_header   Host $host;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header   X-Forwarded-Host $server_name;
        proxy_set_header   X-Forwarded-Proto https;
        proxy_http_version 1.1;
        proxy_connect_timeout  36000s;
        proxy_read_timeout  36000s;
        proxy_send_timeout  36000s;
        send_timeout  36000s;

        # used for view/edit office file via Office Online Server
        client_max_body_size 0;

        access_log      /var/log/nginx/seahub.access.log;
        error_log       /var/log/nginx/seahub.error.log;
    }

    location /seafhttp {
        rewrite ^/seafhttp(.*)$ $1 break;
        proxy_pass http://127.0.0.1:8082;
        client_max_body_size 0;
        proxy_connect_timeout  36000s;
        proxy_read_timeout  36000s;
        proxy_send_timeout  36000s;
        send_timeout  36000s;
        proxy_request_buffering off;
        proxy_http_version 1.1;
    }

    location /seafmedia {
        rewrite ^/seafmedia(.*)$ /media$1 break;
        root /opt/seafile/seafile-server-latest/seahub;
    }

    location /seafdav {
        proxy_pass         http://127.0.0.1:8080;
        proxy_set_header   Host $host;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header   X-Forwarded-Host $server_name;
        proxy_set_header   X-Forwarded-Proto https;
        proxy_read_timeout  1200s;
        client_max_body_size 0;

        access_log      /var/log/nginx/seafdav.access.log;
        error_log       /var/log/nginx/seafdav.error.log;
    }
}