local mailbox, threading disabled, and empty (0 mails) is not displayed, 100% CPU usage
Version: 2.6.1 (didn't try others)
Viewing an empty local mailbox (mbox/mh/maildir) with threading-view disabled does not work. Display area stays gray, not showing an empty list, not even column headings. CPU usage at 100%.
Enabling threading for the mailbox, or putting at least 1 mail into the mailbox works around the problem.
Some debugging shows that lbm_sort_idle_cb() keeps being called over and over in this situation. The difference between working mailboxes (with threading enabled or non-empty) and non-working mailboxes (empty, no threading) seems to be that the working ones have LibBalsaMailboxPrivate.messages_threaded set, even with threading disabled when non-empty. The only value ever passed to libbalsa_mailbox_set_messages_threaded() seems to be TRUE. Maybe messages_threaded can be removed?