My box wanted to update postfix today and the updates appeared to break MIAB but that may be because I was unsure what to answer when the dialog asked what sort of site I wanted.
In any case, for anyone else who runs across this, I was able to fix it by rerunning
curl -s https://mailinabox.email/setup.sh | sudo bash
I saw that today too. If you select the first option (don’t change configuration) during the update, it won’t break.
I was scared of modifying the configuration but have tested messages this morning and all seems to be sending OK on two different MIAB servers.
I guess I didn’t pay enough attention and didn’t see the option to leave everything as is…
I saw that update come in yesterday morning as well, but ran into a different problem. I wasn’t able to get the Postfix update UI to accept any keystrokes, mouse clicks etc. It would also not terminate with a ctrl-C. I had to kill the terminal session, which is not normally something I like doing during an apt-get upgrade.
Fortunately that didn’t seem to break anything in Ubuntu, nor Postfix. I put the postfix packages (3 of them) on hold for now with apt-mark.
In the meantime, I found this article about the oddities of postfix updates and terminal sizes. This seems to describe the problem I was experiencing. Hoping it might help others out of the same situation.