When two messages have identical author and very similar date/time, messages are shown adjacently, without repeating either information. These messages appear 'merged', though will highlight separately when scrolled through.

Starring/unstarring a message should 'split' any merged messages, but currently does not do so reliably. The rationale for this is that the content header applies to the entire (apparent) message, or group of messages, and this includes the star marker.

In addition, if a message is separate, it should not just have a star/no-star status, ie. no repeated author/datetime but a * (or no star); rather, probably the datetime should be repeated.

The code handling this is entirely in the MessageBox class main_view function.