This is more a remark than it is a question.

A couple of days ago, after about two weeks without updating, I updated KaOS. It installed a lot of updates. As I foresaw I wasn't going to be using my box for a couple of days once the updates had finished I shutdown my box, only to power it up again today. Whoa! My viewscreen defaulted to 1024x768 @ 60 Hz (which is really terrible to a look at when you still have a CRT viewscreen).

Quickly I realized somehow the latest proprietary nvidia driver had gotten installed (343), whereas my hardware still relies on the older 304-driver (it's an Nvidia GeForce 8400 GS).

Maybe a prompt? Or maybe just not updating at all from 304 to 343? Usually people who are at 304 are so for a reason.

OK, second report for this. So latest nvidia is dropping support for some cards.

A warning will be added to the .install, so all users on older cards will get a notice they need to switch to 304xx

Can you post your pacman log from that update (not clear from your post if you had nvidia or nvidia-304xx)?

EDIT:

Missed one part of the release notes for nvidia 344.22, it clearly states support is dropped for a series of cards:

demm said,

Can you post your pacman log from that update (not clear from your post if you had nvidia or nvidia-304xx)?

Ah! That's it. I was at 340 before!

From the pacman.log file,

upgraded nvidia-utils (340.32-1 -> 343.22-1)

and,

upgraded nvidia (340.32-1 -> 343.22-1)

My mistake. I honestly thought I was at 304 before.

Warning and instructions are added to nvidia and nvidia-next (in bright, screaming, kind of ugly colors :) :

No use for you since it is after the fact, but next person with older card will see this now on updating.