Update to FreeNAS-11.2-U6 Breaks Plex (w/ Plexpass)

FreeNAS 11.2-U5 system set up cleanly about a month ago.  Only some basic shares and the Plex (w/ Plexpass) plug-in installed via the instructions in the official ixsystems youtube plex plug-in video.

I received a notice about the U6 update for FreeNAS and applied it.  Upon rebooting, Plex is unavailable and attempts to contact its web management interface results in ERR_CONNECTION_REFUSED.

Attempts to update the plug-in and/or the jail via the FreeNAS GUI fail.  For the plug-in, I receive the error in the attached screenshot.

I can't stress this enough:  No other actions were taken.  Merely the update to FreeNAS U6 on a simple FreeNAS install resulted in this state for the Plex (w/ Plexpass) plug-in.

I have, of course, rebooted the FreeNAS box, restarted the plug-in.  And I have tried to assign an IP directly to the Plex jail.  It normally gets the IP via DHCP.  I am able to ping local and remote hosts via jail's shell.