[Users] IMAP account - how to put sent msg in to Sent folder?

[Reid Vail]

Hello Claws-mail forum -

I'm a new Claws user running 3.9.3 on Linuxmint KDE 17, trying to
understand the message placement options/limitation of sent mail
messages.

I have two IMAP accounts: Gmail and Runbox. Both are working fine with 
the client but with the Runbox account I haven't found a way to have 
sent messages placed into the Sent folder for that account.  It will
work if I select a local Sent folder but not Sent folder for that IMAP
account.

Probably I'm missing a config option.  Can you point me in the right
direction please.

thx

Reid