Gridmesh - save preview image as PNG

Godot Version

v.4.5.1 stable

Question

When I make an item in the mesh library of Gridmap unique (because otherwise I can’t save the preview image) and then save the preview image as PNG, the gridmap does not work anymore as intented.
Should I file a bug report?

In the screenshot two weird things happened:

  • the saved image has a red cross.
  • item 1 suddenly has the mesh image of item 0