This has me curious (and that's all it is, curiosity). I have been using Mutt for email on a couple of computers so as to force myself to use and improve my skills in vim. (it's worked, too.)

One computer is Mageia v. 4; the other is Slackware --Current. In both of them Mutt reports "Mutt 1.5.23 (2014-03-12)" as the version.

After reading a mail, the menu bar on the Mageia machine tells me to press 'q" to return to my inbox. On the Slackware machine, it tells me to press "i" to return to the inbox. "q" also works on Slackware, but "i" does not work on Mageia.

Why the difference between the same version of Mutt?

You can find out by how source is built with what patches in both.

I learned that the Mutt version command can provide that information with the correct switches. I'll see what I can find.

I used the

to display the compilation information about the different Mutt installs and piped the output to files, then compared the files using meld.

I could find nothing that I could recognize to explain the differences between the same version of Mutt, but I readily admit that parsing the output to that level of detail was way over my head.

If anyone is interested, I'll post the two outputs of the mutt -vv command, but I don't want to waste the electrons unless someone expresses an interest. As I said, my question was more from curiosity that anything else.