Currently, there are key bindings for next/previous alternatives views.
I use these to flip between HTML and plain-text views of messages. It
works fine, but for one annoyance: there are two keys, and I can never
remember which direction to go (is plain-text "next" or "previous" from
what
I've read about the css styling approach and have been able to tweak the
colors of the message body (using MmMessagesWebView/stylesheet.css), but
I can't seem to find the right way to affect the mailbox list and the
list of messages in a mailbox.
Can someone point me in the right direction?