qt.qpa.plugin error, and core-dump abort (yet A1111 still works)

[crotalidae75]

I'm having an issue crop up in a new install (in a separate A1111 folder), where the webui.sh process spits out out an error referring to qt.qpa.plugin, resulting in a core dump, although A1111 and SD still function. I am running A1111 under Linux (Kubuntu 23.04).

(note: I trimmed the launch script output for brevity)

...

Launching launch.py...
################################################################
Cannot locate TCMalloc (improves CPU memory usage)
Python 3.10.9 (main, Mar  1 2023, 18:23:06) [GCC 11.2.0]
Version: v1.6.0
Commit hash: 5ef669de080814067961f28357256e8fe27544f4
Launching Web UI with arguments: --xformers --medvram --opt-sub-quad-attention
Loading weights [6ce0161689] from /home/crotalus/stable-diffusion-webui.2/models/Stable-diffusion/v1-5-pruned-emaonly.safetensors
Running on local URL:  http://127.0.0.1:7860

To create a public link, set `share=True` in `launch()`.
Startup time: 8.9s (prepare environment: 2.2s, import torch: 2.6s, import gradio: 1.0s, setup paths: 1.1s, initialize shared: 0.1s, other imports: 0.6s, setup codeformer: 0.1s, load scripts: 0.5s, create ui: 0.4s, gradio launch: 0.3s).
Creating model from config: /home/crotalus/stable-diffusion-webui.2/configs/v1-inference.yaml
QObject::moveToThread: Current thread (0x55d534c823d0) is not the object's thread (0x55d534d6ccf0).
Cannot move to target thread (0x55d534c823d0)

qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "/home/crotalus/stable-diffusion-webui/venv/lib/python3.10/site-packages/cv2/qt/plugins" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: xcb, eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx.

Aborted (core dumped)
Applying attention optimization: xformers... done.
Model loaded in 4.2s (load weights from disk: 0.9s, create model: 0.4s, apply weights to model: 2.4s, apply half(): 0.3s, calculate empty prompt: 0.2s).

I figure this is easy enough to fix, but I'm not quite sure how to deal with it. I assume there's a missing package that's needed for venv/lib/python3.10/site-packages/cv2/qt/plugins, but I'm not sure which one.

Any ideas? Thanks in advance.

[webmadmangit]

I have the same error. Interestingly, I am also running Kubuntu 23.04, which is probably where the issue lies- I think there might be a conflict.
The error "QObject::moveToThread: Current thread (0x55d534c823d0) is not the object's thread (0x55d534d6ccf0)" had me suspecting that the error was clashing Qt threads (Kubuntu is built on the Qt framework). Everything seems to work though, so, annoying not destroying. ;-)