MailPortals formerly MailBoxes
MailPortals is an open source unfinished prototype macOS E-mail client which allows the user to view and manipulate multiple mail box folder listings simultaneously.
Here is a video explaining the design goals.
“I have found, no matter how much I categorize and organize my email messages, out of sight is out of mind. My new email client solves this problem by keeping multiple folders and categories of email in sight and in mind. This is an alpha preview of the concept, feedback welcome.”
