[Users] Problem with 2 pane window

[sylpheed at 911networks.com]

Hi,

I use CM 3.11.1 on xUbuntu 14.04.

1. I have the standard 3 pane layout: left: folder, top right: emails
subjects/date and bottom right: the actual email.
2. I press on the down triangle at the extreme right  (next to the
number of emails in the folder / total size of folder) to make it a 2
pane with only the list of messages.
3. I highlight a bunch of email, press the delete key to delete them.

They get moved to the trash, but without doing anything on my part,
I'm back to the 3 pane layout. I want to stay with the 2 pane layout
to do some more deletions...

* Is this the supposed behaviour?
* Am I doing something wrong?
* Is this a bug?

-- 
sknahT

vyS