Get rid of Views. Or allow us to move them below folders. And make them stay hidden!
I don't want them getting in the way of my folders. And it seems every time I open up Mail they get unhidden again.
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Maryann Simpson commented
Ugh, I'm glad it's not just me. Nothing stays collapsed! Everything would be much less irritating if what you told it to hide stayed that way.
That frame on the far right-hand side that takes up a third of the screen is also 'collapsible,' but it pops back open if you so much as navigate away from your mail window.