I have noticed that roundcube 1.6 is currently available in Bookworm (testing) and has been since late July. Could it be backported to Bullseye?
Apart from a desire to have new shiny packages, roundcube 1.4 and 1.5 do not support PHP 8.1, and another web service on my server is prompting me to upgrade my PHP version. I installed PHP 8.1 using the PPA from sury.org and that caused roundcube to stop working because it does not support the later version.
So is it possible to backport, or would it pull down a spider's web of PHP and related dependencies so complex that I may as well upgrade my entire server to Bookworm?