Just noting that I removed the following pre-CR from Section 14, as we have I believe resolved that we cannot address execution environment level issues in this spec after very long debate. That being said, informative text that clarifies that unwrapping unextractable trees are hard to guarantee without special treatment that is not to be normatively expected from the text (but could be provided by implementations in theory) might be useful. I also removed the reference from the example. 

Or we could just keep the remark deleted. 

REMOVED: 

Editorial note:

ISSUE-35:
    
              The specification for wrapKey/unwrapKey does not specify how authors that do not trust  the execution environment may indicate required attributes for keys that are unwrapped. An example is unwrapping a key with a non-extractable key, marking  the newly unwrapped key as non extractable, and then further indicating that all keys unwrapped with the newly unwrapped key are also non-ex