152f5dc897
The problem was that there was a cyclic nesting dependency that was not detected correctly, which led to problems further down the line. See the PR for details. Right now, the zones just disappear when there is an error. This has to be improved at some point, but it outside of the scope of this patch. A regression test that covers this case is added as well. Pull Request: https://projects.blender.org/blender/blender/pulls/111689