Minimize to tray no longer works after update 6.7.1

After updating to version 6.7.1, Calibre no longer minimizes to the system tray on my Windows 10 machine. I have enable system tray icon checked. I've restarted, unchecked it and restarted, checked it again and restarted. This happens whether I am or am not running the content server. Until this update there were no issues with Calibre minimizing to tray.

Suggestions? My thanks for your time.

:help::thanks: