support for 'unread' tab attribute
Thank you for this great extension. I often open multiple links in background tabs before I start to read them. However when there are many tabs it becomes hard to track which ones I have already read. Please add an unread attribute to unread tabs so users can set a style for these kind of tabs and make them visually distinct. The native tabs have an unread="true" attribute when unread and somehow Tree Style Tab has implemented something like this, too.