I have found a minor design flaw that might have to do with ISPConfig plugins (btw: it is great that we have them!) See attached image. Maybe the design broke when there was an update on roundcube's side.. I am using ISPConfig 3.0.3.3 and roundcube 0.3.1-6 (Sorry I've used the wrong forum before)
Thanks a lot! I think I got roundcube from Debian repository and it has been adapted for ISPConfig apparently and as described somewhere here in the forum. How can I update roundcube without breaking something?