The Saved Objects Import API (and corresponding UI feature) attempts to identify missing references when importing objects. For example, the import will fail with a missing_references error when importing a visualization which references an index-pattern that doesn't exist.

This check currently works for direct references of index-patterns and search objects, but it does not handle references of any other saved object type, and it also doesn't handle transitive references.

For example, the API allows for dashboards to be imported which reference non-existent visualizations.

Similarly, the API allows for dashboards to be imported which reference a visualization which in turn references a non-existent index pattern.

Ideally, I think the missing references should handle transient references, and references to other saved object types besides index-pattern and search. I think this should also be an optional condition. The API should allow users to copy the object knowing full well that the reference is missing, if they choose to ignore this warning.

Blocks:

• Spaces - copy saved objects should allow copying without references #43985
• Copy to Space should allow associated index patterns to be changed  #59544