On Mon, 2017-08-07 at 14:05 -0700, Jonathan Ryshpan wrote:
On Mon, 2017-08-07 at 11:59 -0500, Michael Cronenworth wrote:
On 08/06/2017 08:34 PM, Jonathan Ryshpan wrote:
These should be easy to find out but they don't seem to be: What X driver does my system use? If as I suspect it's for intel/Haskel, is it set to use sna or uxa acceleration? Hardware is: 4 core Intel(R) Core(TM) i5-4460 CPU @ 3.20GHz Software is: Fedora-26 with all updates Kernel 4.11.12-200.fc25.x86_64 KDE Frameworks 5.36.0
The "intel" X.org driver is deprecated. I recommend you switch to the "modesetting" driver. With the modesetting driver installed you can remove the intel driver.

The modesetting driver appears to be installed since it's part of the xorg-x11-server-Xorg package, which is installed on my system. But possibly not active. Where are instructions on how to find out whether it's active and, if necessary, how to activate it?

Just after posting this I looked at Xorg.0.log again and found that
    1. the system *is* running the modesetting driver
    2. the modesetting driver's man page says it doesn't do acceleration, which explains why there's no reference to sna or uxa in Xprg.0.log.

    ===> So, I'm left with my original problem, which is why the KDE Plasma desktop often crashes when I close an instance of Firefox with a lot of open windows and/or tabs. I had suspected that it might have something to do with graphics acceleration (there are hints of such problems on the web), but it seems not to be so. Suggestions are welcome. I've reported the crashes to Red Hat's Bugzilla.