In previous question (user "catbill" asked it) the problem wasn't solved. The request is to have option - composing new message in a tab, rather then a new window, because when you open up several such messages, it is a problem to organize these on single monitor/display. Also when you switch away from Thunderbird to different app, when switching back, (especially in Ubuntu) you have to search for that window that contains the "new message" content. In case you have it in tab, for example marked as "New - xyz@mail.com" you have nice overview and not opened plenty of windows, you have to switch between. When switching back to Thunderbird, you are sure, you get back to the started mail writing. It could be an option with right-click to either open in window or tab. Thanks in advance from all people requesting this :)