We have installed nginx-extras, libnginx-mod-http-modsecurity/stable,now 1.0.3-1+b2 and libnginx-mod-http-modsecurity/stable,now 1.0.3-1+b2.
Enabling (uncommenting) the ModSecurity lines produces the following error:
root@xxxxx:~# nginx -t
2025/01/27 09:43:06 [emerg] 80509#80509: "modsecurity_rules_file" directive Rules error. File: /etc/nginx/modsecurity_includes.conf. Line: 8. Column: 81. Invalid input: IncludeOptional /etc/modsecurity/crs/REQUEST-900-EXCLUSION-RULES-BEFORE-CRS.conf in /etc/nginx/sites-enabled/default.conf:26
nginx: configuration file /etc/nginx/nginx.conf test failed
I have tested that if I change IncludeOptional to just Include it works.