Switching sort order from 'd' to 't'

[Felix Finch]

Just noticed an interesting phenomena. I was asked about a several-day-long thread whose most recent message was yesterday, wanted to find the thread beginning, so I switched to 'd' order, found the most recent message, and switched to 't' order while on that message; mutt beeped and went to the last message (in 't' order). Back to 'd' order, found the most recent, switched to 's' order, saw all the messages, went to the very first, switched to 't' order, and it properly stayed in the thread. Or if I stay in 'd' order, find the first in the thread, and switch to 't' order, it does the right thing.

I can sort of comprehend / guess how this might be happening; 't' collapses threads, and because the current message is not directly visible, mutt gets confused, beeps, and goes to the most recent thread. But it seems like a bug.