corrupt mail viewing

[Max Rydahl Andersen]

Hi,

I opened https://github.com/karelzak/mutt-kz/issues/45 a few days ago.

Since then I've seen that even at  revision a50f8a0 I do get corruption of mails when viewing - it just seems to take longer.

I haven't found a  good way to reproduce it, it just happens a few times during the day and the "general fix" is to 
restart mutt-kz.

Note, running with normal mutt I never sees this.

Anything I can do to help track down this ?