A bit strange that I haven't seen anyone else report this, but anyway,
and as a heads-up to those that may run into it: For me, 0.126 would
"crash" with
assertion `tree->sort_info->count(sort_column_id) != 0' failed
as soon as I tried to enter a group. Turned out that this was due to me
having Subject sorting on, and in pre-0.126 that translated to
<int name='header-pane-sort-column' value='10'/>
in preferences.xml, whereas in 0.126 it should be value='8' and '10' is
invalid. Editing preferences.xml took care of it of course, but it
wasn't entirely obvious what was going on, and of course there was no
opportunity to re-set the sort column from within Pan...