It would be nice if Roundcube announced a client id upon connecting to the imap server. It seems as though it would be fairly trivial to add. Thoughts?
Rouncube uses this in imap_debug mode. If you want it to be used always write a plugin. There's libkolab plugin which does that, see https://git.kolab.org/diffusion/RPK/browse/master/plugins/libkolab/libkolab.php;77aa438b51b712996fe5d6c6511ece7b4338e345$97
I wrote a plugin as you suggested; it works perfectly. Thanks for the help.
Could you publish your plugin?