Hi Omen,
Short answer: it's already been fixed.
As you found, the old Sidebar wasn't counting "new" the same way as Mutt.
If you have the time, please test the latest NeoMutt release:
https://github.com/neomutt/neomutt
If that doesn't help, please raise an issue and I'll fix it:
https://github.com/neomutt/neomutt/issues
> > I can verify the behavior does NOT happen with unpatched mutt, so
> > something Debian is adding.
Debian is still using quite an old version of the Sidebar.
I'm working with them to get the latest Sidebar into mutt-patched.
> + if (option(OPTSIDEBAR) && mailbox->msg_unread > 0) {
> + mailbox->new = 1;
> + return 1;
> + }
> +
That code wasn't at fault, it was the counting which happened elsewhere.
But, thanks for looking. It helped me zero-in on the problem.
Rich / FlatCap