Description:
------------
function header() has second parameter = replace;
it turned on by default;
in result it replace all previous "Set-cookie:", including Set-cookie of session. Why it do not look at cookie name and domain? By standard header can contain several Set-cookie...

Yes, I can turn off replace, but for what this parameter in result? I think for remove duplicates in header. For remove duplicates like few "Content-type:", "Date:", "Expires:",... and for remove duplicates in few similar by _name, domain and path_ "Set-cookie:".

Reproduce code:
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session_start();
header("Set-cookie: lang.name=en;expires=Wed, 01 Jan 2020 16:59:02 GMT;path=/;");

Expected result:
----------------
in header:
~~~~~~~~~~~~~
Set-Cookie: sessid=efd66810c22e02211ad598d93aff7d211e7b17b7; expires=Thu, 25 Feb 2010 16:59:02 GMT; path=/
Set-cookie: lang.name=en;expires=Wed, 01 Jan 2020 16:59:02 GMT;path=/;
~~~~~~~~~~~~~

all not duplicated cookies

Actual result:
--------------
in header:
~~~~~~~~~~~~~
Set-cookie: lang.name=en;expires=Wed, 01 Jan 2020 16:59:02 GMT;path=/;
~~~~~~~~~~~~~

only last cookie...