Customizing Mailbox Windows
Eudora OSE automatically remembers the size and screen placement, column and splitter positions of individual mailbox windows.
There is an option in [Options/Prefs window] > Extras > Mailboxes to show or hide the grid lines in the mailbox table of contents. Advanced users and those inclined to tinker might want to read through the Hidden Settings page for still more configuration preferences.
The Who column
Who is a dynamic column that displays the Sender header in all incoming mailboxes, and Recipient in all outbound boxes. It is part of Eudora OSE’s default column palette.