Yes, this needs to be addressed properly, I know! But for now it's
better than nothing.

Previously, Urwid crashed when the foreground style with further
attributes was used as background color in the focus map.

These are ususally the ones I really want to visit, when opening the twt
subject hash tags. The conversation view covers the complete discussion,
including the original twt starting the conversation. The root twt is
missing in the tag search view. In contrast to the search, twts are also
sorted in chronological order in the conversation view, which makes for
a much more convenient user experience, since normal text flow is from
top to bottom.

twtxt.net doesn't support this at the moment, but in the future it might
be a real use case. Currently conversations are just linear and cannot
really break out into different branches like an e-mail thread, but
we've already got it covered.