view not updating when moving messages

this happens sporadically for me, and has been for the last few months. sometimes a restart fixes it, today it did not.

1. select a message to move
   
2. hold option-cmd t
   
3. select destination folder
   
4. message appears to have not moved
   
5. go to destination folder, you can see the message has moved
   
6. go back to original folder, you can see the message is gone

System Version: macOS 10.13.1 (17B1003)
Kernel Version: Darwin 17.2.0

MailMate Version 1.9.7 (5425)