What is the bug or the crash?

When I open a virtual point cloud layer, it shows the classification of the points in the layer symbology. Then I change the styling from Classification to Attribute by ramp > and select Z as the attribute. When I go back to the Classification styling, I have lost all my classes.

This behavior is not present for the COPC files.

Steps to reproduce the issue

Versions

3.41-master

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

No response