Mailbox view helps you to define and setup the look and feel for your mailbox
This shows or hides the Preview Pane in the mail view.
Mark messages as read
Select the delay to mark new messages as “read” when opening them in the preview pane.
On request for return receipt
This option controls the behavior when you open message the sender requested a receipt when you read it.
Expand message threads
When listing messages in threads, this option controls how conversation groups are expanded in the list.
Rows per page
The messages list displays this number of messages at a time (aka a “page”). Increasing this number may result in longer loading times when opening a mailbox folder.
Check all folders for new messages
By default, only the Inbox is checked for new messages periodically. If you have server-side filters installed that will move incoming messages to other folders, you should check this option.