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This content/config mismatch can also happen in other ways, so we should take an approach that handles conflict resolution independent of the copy/paste workflow. The Studio Clipboard use case makes these conflicts more likely to happen, but there are other causes:
Imports will succeed even if the there are references to content groups that don’t exist in the new course.
The Studio UI of some course configuration tries to prevent you from creating illegal states (e.g. you can’t delete a content group if Studio sees you’re using it), but that is not true for all configuration. For instance, you can remove an Assignment Type from the grading policy even if there are Subsections that use that Assignment Type.
These conflicts can be changed by adjusting either the course settings (like adding a missing Assignment Type), or the settings on the content being inserted.
The current Studio approach to this is to mostly ignore these inconsistencies and present the UI as if nothing were selected at all.
There is XBlock-specific functionality for raising validation errors, used at the individual Component level. This is used in a small number of cases, like the LTI XBlock and LibaryContentBlock.
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