Step to repro:
- Open a HDRP project
- Create a shader graph unlit
- Enable "Support VFX" in master node inspector
- Set the base color to red
- Save
- Create a default VFX
- Assign the newly created shaderGraph
- Spawn the newly created VFX in the scene
- Observe the expected red output
- Add an exposed keyword in shaderGraph
- Save the shaderGraph
- Observe the log : "keyword blackboard properties in Shader Graph are currently not supported in Visual Effect shaders. Falling back to default generation path"
- Observe in scene : the rendered particles are now black

Expected:
- The VFX should simply fallback ignoring the unsupported keyword

Bonus:
- The log warning isn't user friendly, usage of the VFX error feedback could be appropriate here.
- The same repro in URP generates compilation error