Letterbox

This is exactly what I’ve been wanting for a long time. Letterbox (formerly MailWidescreen) is a plugin for Mail.app that puts the message preview pane in a 3rd column instead of below the list of messages. This makes it much easier to see the list of messages, it’s easier to read the messages, and it looks great on a wide screen.

I had submitted a feature request to Apple for this, but now it won’t be necessary.

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