System has been running fine for years under all past versions of Xubuntu up through 18.04. The dual monitors are configures without Xinerama so that separate desktop sessions with separate panels launch on each screen.
After the recent upgrade to Xubuntu 18.10, the second monitor is not being recognized. There is a display :0.0, but no active display :0.1.
However, the second monitor is actually active:
* Upon boot it goes from black to a uniform grey
* The mouse can travel onto the second screen (pointer visible) and keyboard input (e.g., volume keys) are active
* Xscreensaver displays on both monitors when it goes active
I have tried to manually start an xfwm4 window manager on the second screen, but this is not possible without a defined :0.1 display.
At the following link I have provided a number of screen shots, config file listings, output from relevant commands and log files to explain in detail what is (or isn't!) happening:
What changed between Xubuntu 18.04 and 18.10 that is keeping the OS from detecting the second screen and configuring it properly and what can I do to rectify the problem? I will provide additional information as needed.
Suggestions are truly appreciated. Thanks for any help you can offer.