Improve keyboard navigation with the Escape key. Two areas:

(1) When I search for something within my mailbox, I want to hit the Esc key to go back to the inbox.

(2) Sometimes pressing Esc doesn't "Go back". Ie, it requires me to click within the main content window. A common case of this is when I will open a message, I'll press Esc once, and it will minimize the current email. But pressing Esc a second time WILL NOT go back to the Inbox. For me to go back to the inbox, I will have to click in the area where the now-minimzed email was.