Sporadic keyboard stalls and repeats with libinput in Xorg

[Ken Moffat]

This is weird - *most* of the time libinput (Beyond
Linuxfromscratch, recent builds) works fine on my (desktop, running
Xorg, usually icewm) machines.  And then from time to time - like
this evening, after I awakened this machine from suspend - I starts
stalling.  Usually characters will disappear while I am editing in a
term, and then eventually appear if I wait.  Sometimes characters
seem to get totally lost.  Other times, the last character repeats
many times.

I've seen this in 1.10.7, 1.10.8 on two machines, but those were
running early -rc kernels so I assumed it might be a kernel problem.
But the current machine is now running linux-4.17.2 (it was running
4.17.1 when I built the system).  In 4.17.1 it happened at least
twice, and tonight it has happened again.  This is with 1.11.0.

I found a suggestion to run libinput-debug-events, but I never have
that running when the problem hits, and I'm not sure what I should
be passing to it (if I mouse to it during a stall, its display fills
up with mouse moves and scrolls out of view).  And I've forgotten
how to determine which /dev/input/event device the keyboard is
using.

Any suggestions, please ?

ĸen
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