When I toggle Window Overview on my Lenovo ThinkPad T510, the background appears to turn white, along with the profile picture in Kickoff. Lockscreen also turns white. Not sure what's up because another user profile wasn't experience the same thing.

Not exactly sure when it happened, but it was most likely after I downgraded Mesa from 22 (from Ernst's Mesarc PPA) to 21 to fix the issue with 22 not supporting older graphics hardware, like the one with 1st gen Intel Core. I was using 22 from Mesarc PPA because there was an issue with 21 from the official repo where the laptop would freeze up, although that resulted in using Llvmpipe instead of my T510's Intel HD.

Operating System: Kubuntu 22.04
KDE Plasma Version: 5.24.3
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.2
Kernel Version: 5.16.0-18.1-liquorix-amd64 (64-bit)
Graphics Platform: X11
Processors: 4 × Intel® Core™ i7 CPU M 640 @ 2.80GHz
Memory: 7.6 GiB of RAM
Graphics Processor: Mesa Intel® HD Graphics

I opened a bug 452065 before I realized that another user account wasn't affected.