Comment # 25 on bug 1134805 from Mindaugas Baranauskas

Created attachment 804902 [details]
screenshot with artifacts, radeon driver

I can see artifacts with /etc/X11/xorg.conf.d/50-device.conf:

Section "Device"
  Identifier "Default Device"
  Driver "radeon"
  Option "AccelMethod" "XAA"
  Option "EnablePageFlip" "on"
EndSection

Though yes, XAA was ignored as in /var/log/Xorg.0.log I see:
[   429.878] (II) Loading sub module "exa"
[   429.878] (II) LoadModule: "exa"
[   429.878] (II) Loading /usr/lib/xorg/modules/libexa.so

> inxi -GxxCS
System:    Host: localhost Kernel: 5.0.11-1-default i686 bits: 32 compiler: gcc
v: 8.3.1 Desktop: KDE Plasma 5.15.5 
           tk: Qt 5.12.3 wm: kwin_x11 dm: SDDM Distro: openSUSE Tumbleweed
20190509 
CPU:       Topology: Single Core model: Intel Celeron D bits: 64 type: MCP
arch: Netburst Presler rev: 5 L2 cache: 512 KiB 
           flags: lm nx pae sse sse2 sse3 bogomips: 6133 
           Speed: 3067 MHz min/max: N/A Core speed (MHz): 1: 3067 
Graphics:  Device-1: Advanced Micro Devices [AMD/ATI] RC410 [Radeon Xpress
200/1100] vendor: Intel driver: radeon v: kernel 
           bus ID: 01:05.0 chip ID: 1002:5a61 
           Display: x11 server: X.Org 1.20.4 driver: radeon compositor:
kwin_x11 resolution: 1440x900~60Hz 
           OpenGL: renderer: ATI RC410 v: 2.1 Mesa 19.0.3 direct render: Yes