Black Viewport on Linux

[ScatteredRay]

I'm getting a black viewport running on Linux. Initially, I found that pxr/garch doesn't support EGL, and can't capture the context on wayland. But forcing to run under XWayland, I get a black viewport.

Here is my console output:

Settings: /home/indy/.usdtweak_gui.ini
AMD
AMD Radeon RX 6800 XT (radeonsi, navi21, LLVM 18.1.8, DRM 3.54, 6.6.45)
OpenGL 4.6 (Compatibility Profile) Mesa 24.1.5
GLSL 4.60
USD 2405
glxContext: 0x21f2f40
PXR_PLUGINPATH_NAME:
rawContext1
Reading blueprints
Blueprints ready
Warning: In image "/home/indy/dev/RenderWitch/assets/venice_sunrise_4k.exr" mip level 1 does not exist [usdtweak]

I tried a capture from RenderDoc, and don't seem to see any element from the scene in the capture.

Any thoughts on things I could do to start to diagnose this issue?