Lost my mailbox?

[wowhelicase]

Hello all:

This is the dumbest thing, but when I click on mailboxes with the Addon package loaded, nothing happens. I have identified that RealUI Inventory is the issue, and I have draggable frames on, so I suspect I dragged the mailbox off-screen somewhere by accident, and I cannot get it back.

Any idea how to reset the mailbox window's position? Either in-game or in a setting in a file? Thanks in advance!