Comment 1 for bug 62804

The format of the listing is given by the attach_format configuration variable. The default for this includes a fixed-width entry for the description (which is the e-mail subject) of "%.40d".

You can remove the .40 to allow the subject to be any length, but if the subject is very long, it can push the mimetype, encoding and size information off the side of the screen. The reason this isn't a problem with the main mailbox index is that the subject is the last thing on the line, and so is simply truncated. You might be able to find a completely different attach_format setup that you like better which also has the description at the end of the line.