Well this fixes my problem with mysteriously disappearing "reply to all" link.
I edited "Plugins and Products" => "Cyb - PM System Enhancements - RA" (hook private_complete)
Find
Code:
if ($cyb_confirmmulticc ==';')
replace with
Not sure why that check is made or why it's needed. The "recipients" list is only displayed if there are more than one recipients anyway. Maybe it's my 3.6.x version or some other template problems I was having.