When viewing a diary entry in preview mode, switching dates does not switch the entry

[SteveDinn]

To reproduce:

• Have at least two diary entries
• Show one diary entry in 'preview mode' rather than 'markdown editor mode'
• Select another diary entry. i.e., navigate to the previous or next day, or select a different entry from the list
• Notice that despite the date changing, the displayed entry does not change

[danielroehrig]

Oh. OH! I am pretty sure, that has always been broken and nobody ever noticed. At least not me, because I never use that functionality. But that's bad. I still hate the front end and I dread trying to fix it, but I put it on the list. Thanks for the bug report!