SUMMARY
When using the Wayland version of Plasma on Kubuntu 22.04, all desktop elements will freeze if I am not currently moving the mouse, making the desktop nigh unusable. The splash screen gets stuck almost immediately, context menus are laggy and difficult to select options in, and if I swipe my mouse over my task manager icons: The selected program will be two or three icons away from where my mouse actually stops.
I've found two other users with the same problem so far, their specs are included below. The main correlation is that we are all on 22.04 with an Nvidia GPU. I myself am using the Kubuntu-Backports-Extra PPA which puts me on Plasma version 5.25.5, but still face the exact same issue as the other users on 5.24.

Apologies if this is a Kubuntu bug rather than a KDE/Plasma one, I'll make a bug report on their end if necessary.


STEPS TO REPRODUCE
1. Use Kubuntu 22.04 on a Nvidia GPU
2. Install plasma-workspace-wayland and restart.
3. Select Wayland in SDDM and login.

OBSERVED RESULT
Splash screen will immediately freeze upon appearing if the mouse is left stationary. Right clicking and moving mouse on top of an item in the context menu will leave the wrong item selected until the mouse is jiggled. Same for the task manager.

EXPECTED RESULT
All items should animate as normal.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu 22.04
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.98.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
My full specs:
Operating System: Kubuntu 22.04
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.98.0
Qt Version: 5.15.3
Kernel Version: 5.15.0-47-generic (64-bit)
Graphics Platform: X11
Processors: 6 × Intel® Core™ i5-8600K CPU @ 3.60GHz
Memory: 15.6 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 3080/PCIe/SSE2
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7B61
System Version: 1.0

Reddit user 1:
Nvidia driver: 510.85.02
Wayland: 4:5.24.4-0ubuntu1
Operating System: Kubuntu 22.04
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version: 5.15.0-43-generic (64-bit)
Processors: 16 × AMD Ryzen 7 5800X 8-Core Processor
Memory: 125.7 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 3090/PCIe/SSE2

Reddit user 2:
Operating System: Kubuntu 22.04
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version: 5.15.0-46-generic (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 3600 6-Core Processor
Memory: 31.3 GiB of RAM
Graphics Processor: NVIDIA GeForce GTX 1660 SUPER/PCIe/SSE2

(Nvidia driver 515.65.01-0ubuntu0.22.04.1)

/r/Kubuntu post: https://www.reddit.com/r/Kubuntu/comments/wizmnh/wayland_on_2204_hangs_all_screen_updates_unless/