Mail.app notifications done right.
Herald is a plugin for Mail.app that goes far beyond OS X's built in notifications.
Herald allows you to perform common actions directly from within the notification window, including deleting, initiating replies, or marking as read. And Herald's appearance is customizable, so you can tailor it to your own taste.
Herald is a free download for El Capitan. If you like it, please consider donating!
Quick Action Toolbar
Easily perform actions on messages: mark as read, initiate replies, delete, and more, right from within the notification.
Messages are grouped into a single notification window to prevent clutter. Flip through messages with a single click.
Adjust window size, style, font, position, color, shadow, and transparency.
Enable Specific Mailboxes
Enable notifications for all mailboxes or only specific mailboxes of your choosing.
Automatic or Manual Dismissal
Configure Herald to dismiss notifications after a set period of time or stay on screen until the window is clicked.
View Entire Message
A scrollable message window means you can view the full message without having to switch to Mail.
From my testing, it works as advertised. I especially enjoyed the full message-reading capability.
A rare moment here folks, we've cast our critical Top Tech eye over this app, and we just can't find anything we don't like!
The coolest mail plugin tool ever.