Compiling our own nginx yields issues with ISPconfig checks

Ever since we compiled our own freenginx from source on our debian 12 servers (because we needed extra modules unavailable in the packaged releases), we get mails from root seemingly triggered by ispconfig. The emails say the following;

Code:

localhost.localdomain - 27.08.2024-16:14 - WARNING - Could not check Nginx version, did not find version string in nginx output.

While there are no issues whatsoever getting the version of nginx;

Code:

# nginx -v
nginx version: freenginx/1.27.3

# nginx -V
nginx version: freenginx/1.27.3
built by gcc 12.2.0 (Debian 12.2.0-14)
built with OpenSSL 3.0.13 30 Jan 2024
TLS SNI support enabled
configure arguments: --sbin-path=/usr/sbin/nginx --with-cc-opt='-g -O2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -flto=auto -ffat-lto-objects -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -fPIC -Wdate-time -D_FORTIFY_SOURCE=3' --with-ld-opt='-Wl,-Bsymbolic-functions -flto=auto -ffat-lto-objects -Wl,-z,relro -Wl,-z,now -fPIC' --prefix=/usr/share/nginx --conf-path=/etc/nginx/nginx.conf --http-log-path=/var/log/nginx/access.log --error-log-path=stderr --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --modules-path=/usr/lib/nginx/modules --http-client-body-temp-path=/var/lib/nginx/body --http-fastcgi-temp-path=/var/lib/nginx/fastcgi --http-proxy-temp-path=/var/lib/nginx/proxy --http-scgi-temp-path=/var/lib/nginx/scgi --http-uwsgi-temp-path=/var/lib/nginx/uwsgi --with-compat --with-debug --with-pcre-jit --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_v2_module --with-http_v3_module --with-http_dav_module --with-http_slice_module --with-threads --with-http_addition_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_secure_link_module --with-http_sub_module --with-mail_ssl_module --with-stream_ssl_module --with-stream_ssl_preread_module --with-stream_realip_module --with-http_geoip_module=dynamic --with-http_image_filter_module=dynamic --with-http_perl_module=dynamic --with-http_xslt_module=dynamic --with-mail=dynamic --with-stream=dynamic --with-stream_geoip_module=dynamic --add-dynamic-module=/usr/src/installs/ngx-fancyindex

a search for the strings used in those emails pointed me to ispconfig code.