User-Agent:       Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
Firefox/60.0
Build Identifier: 

Rows of black and white bars flash up when mouse moved around on password entry
screen. Seen both with laptop screen and external monitor. Using nouveau
driver.

[I don't know if this is a KDE or X11 issue]

Machine is Dell Precision M4800 laptop with 3200x1800 screen and external
3840x2160 AOC U2868PQU monitor.

KDE Plasma Version 5.12.6
KDE Frameworks version 5.45.0

kernel version 4.12.14-lp150.12.48-default

/etc/os-release containsrparkins@rparkins48:~> cat 

NAME="openSUSE Leap"
VERSION="15.0"
ID="opensuse-leap"
ID_LIKE="suse opensuse"
VERSION_ID="15.0"
PRETTY_NAME="openSUSE Leap 15.0"
ANSI_COLOR="0;32"
CPE_NAME="cpe:/o:opensuse:leap:15.0"
BUG_REPORT_URL="https://bugs.opensuse.org"
HOME_URL="https://www.opensuse.org/"


Reproducible: Always

Steps to Reproduce:
1. boot up machine, wait for password entry screen
2. move mouse around
3.
Actual Results:  
Rows of black and white bars flash up

Expected Results:  
No change in screen until I type something or click on a button