Igor, Thank you for your reply.
That is one solution, or edit the file manually would for for a while at least..
At the top of both files:
/etc/psa-webmail/horde/horde/php.ini
/etc/psa-webmail/roundcube/php.ini
is the text:
; ATTENTION!
;
; DO NOT MODIFY THIS FILE BECAUSE IT WAS GENERATED AUTOMATICALLY,
; SO ALL YOUR CHANGES WILL BE LOST THE NEXT TIME THE FILE IS GENERATED.
I am curious what events regenerate these files (other than initial install)
Thanks!