Bug 471852

SUMMARY
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STEPS TO REPRODUCE
1.  Only be using Nouveau Nvidia driver, (i.e. as after a fresh install of KDE Neon Unstable)
2.  On login screen, change from Plasma (X11) to Plasma (Wayland)
3.  Login

OBSERVED RESULT
1)  There's a momentary square of distorted colors in the upper left before the desktop renders, after which the screen goes black.
2)  The desktop is then rendered, looks fine, but almost immediately the mouse pointer freezes and then the entire desktop does, so that it's entirely unusable, with different distorted parts of the screen showing over the desktop with each login.
3)  After force-shutting down the entire laptop, and restarting, (note: before the KDE Neon logo comes up, there was mention of some failure of the nouveau driver, (after two other ACPI errors) - I believe this was one of my other bug reports) if you leave the login screen set to Plasma (Wayland) you'll see a repeat of the above every time.  If you change to Plasma (X11) you will have a fully functioning desktop.
4)  Note: after installing the (535) proprietary Nvidia drivers, (via sudo ubuntu-drivers install) Plasma (Wayland) seems to work fine, so it's only an issue with the nouveau drivers.  


EXPECTED RESULT
A fully functioning desktop.


SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma:  KDE Neon Unstable, (just installed fresh from Live iso today - 2023-07-01).  Note: did do a pkcon refresh and sudo pkcon update, which I think was after the above kept happening, and am now running the 535 proprietary Nvidia drivers, so can no longer replicate the issue, so the versions in About System might be newer than those that were in place when the above was happening.  That being said, About System reads:
- KDE Plasma Version: 5.27.80
- KDE Frameworks Version: 5.240.0
- Qt Version: 6.5.1
- Kernel Version: 5.19.0-46-generic (64-bit)
- Graphics Platform: Wayland
- Processors: 8 × Intel® Core™ i7-4710HQ CPU @ 2.50GHz
- Memory: 15.5 GiB of RAM
- Graphics Processor: llvmpipe
- Manufacturer: ASUSTeK COMPUTER INC.
- Product Name: G751JT
- System Version: 1.0

(available in About System).  
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION