Created attachment 170533 [details]
an image showing the blurred shadow that appears after the panel expands.

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SUMMARY
Visual artifact: A blurred shadow appears beneath the panel after it expands to full-length. This occurs in two scenarios:

1. When a window is maximized.
2. When a non-maximized window overlaps the panel, causing it to expand.

STEPS TO REPRODUCE
1. 
2. 
3. 

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.3.0
Qt Version: 6.7.1

ADDITIONAL INFORMATION