In Mail.app I use IMAP folders with deep nesting provided to me by a service. Result: long folder names. How can I freely resize the left "mailbox list" (command+shift+M) pane? Apple seems to "know" what is the maximum size that is "good for me" and stops resizing after a certain point.. (?!)
To reproduce: just try to resize the left pane dragging it to the right..
Effect of me: renders a certain type of IMAP service.. basically useless because of a limitation in the client.