I followed @philm’s instructions in his post (#86) at Dropping all legacy and older Nvidia drivers ?!? - #86 by philm and that got NVIDIA GLX working again with XOrg for me with the 340xx driver series.
Thank you @philm!!!
P.S.
cat /proc/driver/nvidia/gpus/0000:01:00.0/information
Model: GeForce GTX 560
IRQ: 136
GPU UUID: GPU-d4b3bf21-97b7-dbde-1ef5-21cf6b4445b6
Video BIOS: 70.24.18.00.00
Bus Type: PCIe
DMA Size: 40 bits
DMA Mask: 0xffffffffff
Bus Location: 0000:01:00.0
cat /proc/driver/nvidia/version
NVRM version: NVIDIA UNIX x86_64 Kernel Module 340.108 Wed Dec 11 11:06:58 PS
T 2019
GCC version: gcc version 10.2.0 (GCC)
grep ‘NVIDIA GLX’ /var/log/Xorg.0.log
[ 19.379] (II) NVIDIA GLX Module 340.108 Wed Dec 11 14:26:50 PST 2019
uname -a
Linux calypso 5.10.2-2-MANJARO #1 SMP PREEMPT Tue Dec 22 08:14:42 UTC 2020 x86_
64 GNU/Linux