missing opentelemetry headers on auth_request location

Describe your environment EKS 1.24 Nginx:

nginx version: nginx/1.21.6
built by gcc 12.2.1 20220924 (Alpine 12.2.1_git20220924-r4)
built with OpenSSL 3.0.8 7 Feb 2023
TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx --conf-path=/etc/nginx/nginx.conf --modules-path=/etc/nginx/modules --http-log-path=/var/log/nginx/access.log --error-log-path=/var/log/nginx/error.log --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --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-debug --with-compat --with-pcre-jit --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_addition_module --with-http_geoip_module --with-http_gzip_static_module --with-http_sub_module --with-http_v2_module --with-stream --with-stream_ssl_module --with-stream_realip_module --with-stream_ssl_preread_module --with-threads --with-http_secure_link_module --with-http_gunzip_module --with-file-aio --without-mail_pop3_module --without-mail_smtp_module --without-mail_imap_module --without-http_uwsgi_module --without-http_scgi_module --with-cc-opt='-g -O2 -fPIE -fstack-protector-strong -Wformat -Werror=format-security -Wno-deprecated-declarations -fno-strict-aliasing -D_FORTIFY_SOURCE=2 --param=ssp-buffer-size=4 -DTCP_FASTOPEN=23 -fPIC -I/root/.hunter/_Base/d45d77d/aab92d8/3b7ee27/Install/include -Wno-cast-function-type -m64 -mtune=generic' --with-ld-opt='-fPIE -fPIC -pie -Wl,-z,relro -Wl,-z,now -L/root/.hunter/_Base/d45d77d/aab92d8/3b7ee27/Install/lib' --user=www-data --group=www-data --add-module=/tmp/build/ngx_devel_kit-0.3.1 --add-module=/tmp/build/set-misc-nginx-module-0.33 --add-module=/tmp/build/headers-more-nginx-module-0.33 --add-module=/tmp/build/ngx_http_substitutions_filter_module-b8a71eacc7f986ba091282ab8b1bbbc6ae1807e0 --add-module=/tmp/build/lua-nginx-module-0.10.21 --add-module=/tmp/build/stream-lua-nginx-module-0.0.11 --add-module=/tmp/build/lua-upstream-nginx-module-8aa93ead98ba2060d4efd594ae33a35d153589bf --add-module=/tmp/build/nginx_ajp_module-fcbb2ccca4901d317ecd7a9dabb3fec9378ff40f --add-dynamic-module=/tmp/build/nginx-http-auth-digest-1.0.0 --add-dynamic-module=/tmp/build/nginx-influxdb-module-5b09391cb7b9a889687c0aa67964c06a2d933e8b --add-dynamic-module=/tmp/build/nginx-opentracing-0.19.0/opentracing --add-dynamic-module=/tmp/build/ModSecurity-nginx-1.0.3 --add-dynamic-module=/tmp/build/ngx_http_geoip2_module-a26c6beed77e81553686852dceb6c7fdacc5970d --add-dynamic-module=/tmp/build/ngx_brotli

Using the version: registry.k8s.io/ingress-nginx/opentelemetry:v20230312-helm-chart-4.5.2-28-g66a760794@sha256:40f766ac4a9832f36f217bb0e98d44c8d38faeccbfe861fbc1a76af7e9ab257f when i set a auth location like:

location = /auth {
    internal;

    opentelemetry on;
    opentelemetry_propagate;
    opentelemetry_trust_incoming_spans on;
    proxy_pass http://authorizer;
}
location / { 
    opentelemetry on;
    opentelemetry_propagate;
    opentelemetry_trust_incoming_spans on;

    auth_request  /auth;
    proxy_pass    http://application;
}

The open telemetry headers are available only for the location / backend but not for the location /auth backend.

What is the expected behavior? I want to have the same trace id in both backends: (application and authorizer)

What is the actual behavior? I have only the trace id generated for the application, but the open telemetry headers are not sent to the authorizer app.

open-telemetry / opentelemetry-cpp-contrib

missing opentelemetry headers on auth_request location #270