@wilbr Huh? I certainly *do* expect it to indicate what thing I am currently viewing. That's a fairly crucial part of UX.
@joepie91 just in terms of less clutter, having recently reinstalled Thunderbird myself. Sure you want to know what you're looking at but modern design relies less on extraneous lines and text when a thoughtful icon or bold could do. Packing a lot of text and panes and grids and stuff into a small space feels busy.
@wilbr (Also: I don't know where this assumption comes from that things must be redesigned to remove information. That isn't what I'm looking for at all.)