id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
2100	Expires directive does not allow to add immutable variable to Cache-Control header	selivan@…		"`expires` directive sets 2 headers at once: Expires and Cache-Control.

Cache-Control is set to 'max-age=NNN', and can not be changed: using `add_header` just produces 2 Cache-Control headers.

I suggest to add optional flag `[no_add_cache_control]`, that will stop `expires` directive from adding Cache-Control header and allow configuration like this:

{{{
expires no_add_cache_control 1d;
add_header Cache-Control ""public, max-age=86400, immutable"";
}}}

Cache-Control header has more variables than just `max-age`, it would be nice to be able to change it while still using Expires header for user agents that do not respect Cache-Control.

For example, `immutable` flag is useful to stop browsers like Firefox and Safari from creating requests for cached resources, just to get 304 response.
"	enhancement	closed	minor		nginx-core		duplicate		selivan@…		nginx/1.18.0