From the bug report , which also has a screen shot mock up "This would make it easier to identify the folders of diffrent mail accounts. This would also make sense for the top account nodes."
(Going forward...)Please remember where we are here, in Connect, is a place for discussion and voting. For support please see https://support.mozilla.org/en-US/questions/new/thunderbird
@Otoro Which of the ideas you named is the same as https://connect.mozilla.org/t5/ideas/calendar-category-see-the-category-color-on-both-the-calendar/idi-p/28160, i.e. Bug 1362121 - Support new RFC-7986 COLOR property (calendar color) ?
