Thinking the unsupported nvidia 340.108 driver for my twin PCI-e cards could well be the cause, I decided that my upgrading to Chimaera would be a good opportunity to see if the nouveau driver worked as well as it did in the Daedalus live-iso I had tested some time ago.

But it was (indeed) a Chimaera.

After a few hours of trying to get the two card / three screen layout to work as it was supposed to, I called it a night.

I had not had this much fun since I first spent a couple of days to get a properly working xorg.conf in a version of PCLinuxOS.
That was many years ago, may be too old for all that now.

At the time the effort proved to be well worth it as I was able to use the same configuration file from Jesse to Beowulf by simply dropping it in place, no questions asked.

But nouveau would have none of it and the xorg-config generated file was not a solution.

This morning, before I restored my Beowulf image I decided to see if whatever problem I had in front of me had been solved/taken care of in Daedalus, so I went ahead with the upgrade.

Went by witout much ado and although few desktop settings got mangled (conky panel and xfce4-panel placement and transparency) the three screens were recognised and working as intended fron the get-go, with Right click -> Open [ Terminal or root Thunar ] here is working as expected.

So, for the time being everything is well enough, time will tell.

Many thanks to the developers/maintainers involved in/with Devuan and nouveau: the problems I came across did not get fixed by themselves.

Best,

A.

Finally decided to upgrade from Beowulf to Chimaera.

~/Desktop$ uname -a
Linux devuan 5.10.0-29-amd64 #1 SMP Debian 5.10.216-1 (2024-05-03) x86_64 GNU/Linux
~/Desktop$ 

But there are a couple of things that the upgraded version of Xfce seems to have broken.

eg:
Right click -> Open [ Terminal or root Thunar ] here does not work as expected ie: as it did before the upgrade.

Instead of opening where the pointer is (one of the three monitors) it always opens the selection in the centre monitor.
I have not been able to find out how to fix it.

I'd appreciate some input on this.

Thanks in advance.

Best,

A.