I did some deeper debugging. Even the nginx log inside the container shows no useful information about whats going on
root@docker5-web-only:/var/log/nginx# tail -f access.log | grep 500
[06/Mar/2026:08:51:45 +0000] "``forum.netzwissen.de``" 10.10.10.21 "POST /t/1431/move-posts HTTP/1.0" "Mozilla/5.0 (X11; Linux x86
_64; rv:148.0) Gecko/20100101 Firefox/148.0" "topics/move_posts" 500 432 "``https://forum.netzwissen.de/t/begehung-quartierszent
rum-mettingen/1431/3" 0.053 0.052 "mainmod" "-" "-" "-" "-" "-" "-"
I would guess that the root cause lies somewhere behind, e.g. in the database request from postgres (we use separate containers and a dedicated postgres server)