While the ability to save multiple emails to the same matter at a time would be preferable, it would also be a nice option to be able to keep the email add-in window open. If you are adding multiple emails at a time to the same matter or different matters (such as catching up on a day's worth of emails or even a week), it would save time if the window did not close every time and go through the log-in or find credentials step each time, and saving multiple extra key strokes. If keeping it open was optional, those who want it open can do so and those who do not, do not.