ParaView on Ubuntu 22.04 shows empty transparent window — tried multiple versions

Dear ParaView Community,

I’ve been trying to install and run ParaView on Ubuntu 22.04 (CPU-only system with Mesa/llvmpipe), but I consistently encounter the same issue:
When I launch ParaView, the window opens but remains completely blank and transparent — no splash screen, no menus, no render view. Just a transparent shell.

Here’s what I’ve tried:

Tested ParaView versions 5.12.1, 5.11.1, and 5.10

Used both the standard (GUI) builds and OSMesa headless builds

Installed and confirmed working Mesa (llvmpipe) with glxgears

Set the following environment variables:

export LIBGL_ALWAYS_SOFTWARE=1
export MESA_GL_VERSION_OVERRIDE=3.3
export QT_QPA_PLATFORM=xcb

Verified OpenGL is working:

OpenGL renderer string: llvmpipe (LLVM 15.0.7, 256 bits)

Despite all this, the GUI still opens as a transparent/empty window.

Has anyone else encountered this? Is there a known workaround for CPU-only systems on Ubuntu 22.04?

Thanks in advance for any insights or suggestions.

Please test with ParaView 6.0 RC1 binary release from https://www.paraview.org/download/