kustomize build fails because a patch file sits outside the kustomization's directory. What does the default load restrictor require?

Answer: Every referenced file must be inside the kustomization's directory tree

Explanation

The default, LoadRestrictionsRootOnly, stops a kustomization from reading files outside its own tree. resources can still point at another directory that has its own kustomization file. '--load-restrictor LoadRestrictionsNone' turns the check off, which is best avoided.