Bug 485001

Created attachment 168116 [details]
Screenshot of artifacts, with inset zoomed in

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SUMMARY
When the graphs are drawn on the System Monitor, random artifacts show up above or on the graph drawing. It is most noticeable when "Fill opacity" is set to "100%".  The stray dots change each time the graph is redrawn. This creates an ugly, distractiing effect.  

It looks like a video bug, but it doesn't change when I move the window or display it internal vs. external monitors.  It may still be a low-level drawing bug, but I haven't noticed the problem on any other apps.  

I didn't see this problem in 5.27.x.  It showed up when I upgraded to Plasma 6.0.0.  I thought it was a Wayland bug at first, but I also see it on X11.

STEPS TO REPRODUCE
1. Open the History pane
2. Make sure CPU graph options have "Fill opacity: 100%"
3. See dots appear above the graph

OBSERVED RESULT
Graph has ugly dots around the edges.  (See attached screenshot.)

EXPECTED RESULT
Pretty graph.

SOFTWARE/OS VERSIONS

Operating System: KDE neon 6.0
KDE Plasma Version: 6.0.3
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.3
Kernel Version: 6.5.0-26-generic (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-10610U CPU @ 1.80GHz
Memory: 15.2 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics
Manufacturer: LENOVO
Product Name: 20UCS4TR00
System Version: ThinkPad X1 Yoga Gen 5

ADDITIONAL INFORMATION