Because I usually know which folder contains what I'm searching for, 98% of the time I'm able to find what I'm looking for quickly using the filter bar. This en

Because I usually know which folder contains what I'm searching for, 98% of the time I'm able to find what I'm looking for quickly using the filter bar. This ends up being a much better experience for me than the search tool. Because the filter bar doesn't put you in a new UI, you keep the benefits of continuing to use list/message panes: (a) UI context not lost, (b) the matches shows as a list, not the hard-to-scan context results that are default in search, (c) clicking on matches shows the email in the message panel, allowing you to quickly find the right message. The filter bar also lets you quickly toggle if your filter term is the recipient, sender, subject line, or message body. I wish the UI design of the filter bar could be the basic search tool, expanded in some way to allow for search within multiple/all folders, and slightly more complex searches (specify filters for person AND subject line). Perhaps when you click on the profile in the mailbox panel, the filter bar continues to show, letting you search on all folders. If in a parent folder, there could be a checkbox to show/filter all messages in child folders. The existing search UI could still exist and be used for advanced searching.