I'm having trouble getting to my custom mailboxes in the Mail app. When I interact with the Mailboxes table, I can find where it says on my Mac. This group of mailboxes is collapsed. There seems to be no way to expand them. I tried VO space, pressing right arrow by itself and even moving the mouse cursor and clicking on it. None of these strategies have worked. Its still collapsed and my custom mailboxes are hidden because of that. Any ideas or suggestions?