Confirmed working on 2.3.0, however I made a few slight modifcations in the manner that the private message previews are displayed. I noticed that you were utilizing
nl2br() to convert new lines into <br> which can stretch the layout so I removed the call to that function and added a
str_replace() to remove carriage returns "\n" and new lines "\n" from the $lastpmstuff['preview'] variable.