Created attachment 167547 [details]
Screen recording for the mentioned panel

SUMMARY
The panel (or taskbar in this case) floats by default, and unfloats when there's a window nearby, or a window maximized. 
I notice there's an animation being played when the panel switches between float / unfloat state. However the animation isn't quite smooth...


STEPS TO REPRODUCE
1. Have a floating panel at the side of your screen (in my case it's at the top of my screen)
2. Open a window, drag it to and away from the panel, the panel switches between floating and "not floating" state
3. Or, have a window maximized in a workspace (workspace 1), and another workspace (2) with no any window
4. Then switch between workspace 1 and 2

OBSERVED RESULT
The panel plays an animation when it floats / unfloats. The animation seems glitchy, ugly, and not smooth at all. 

EXPECTED RESULT
It should be smooth. 

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Arch Linux
(available in About System)
KDE Plasma Version: 6.0.2
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
This is probably not a bug, but I think it needs optimization. 
Additional hardware information: 
Graphic Card: NVIDIA GT 750M with proprietary driver

In addition the panel seems to be flashing in the recorded video (in the first second and when I switch between workspaces). I don't know why that happens, but the flashing appears only in the recording and not to my own eyes.