Application fails to launch: qt.qpa.xcb: could not connect to display :0

[Paul-Haynes]

Upon attempting to launch by running "python3 -u scripts/render/run.py --flagfile res/flags/run.flags" the following error occurs:

qt.qpa.xcb: could not connect to display :0
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" 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: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.

Fatal Python error: Aborted

Current thread 0x00007f86a2f57740 (most recent call first):
File "dep.py", line 282 in main
File "/usr/local/lib/python3.7/dist-packages/absl/app.py", line 251 in _run_main
File "/usr/local/lib/python3.7/dist-packages/absl/app.py", line 300 in run
File "dep.py", line 315 in
Fatal Python error: Segmentation fault

Current thread 0x00007f86a2f57740 (most recent call first):
File "dep.py", line 282 in main
File "/usr/local/lib/python3.7/dist-packages/absl/app.py", line 251 in _run_main
File "/usr/local/lib/python3.7/dist-packages/absl/app.py", line 300 in run
File "dep.py", line 315 in

I have followed the Docker installation instructions. Incidentally I have previously used the application and I think I encountered the same error and managed to resolve however that was many months ago and don't recall how. I think the issue is related to Docker / X11 forwarding. This is occurring using Ubuntu 18.04.5 LTS with an Nvidia GPU.