Cannot convert subtask to story

[crowdds]

I go through the wizard to convert a subtask to a story, but just get Server 500 error when clicking "Finish" on the last step:

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• Error type: 500 - Internal server error
• Log reference: 0d710ddf-9a71-48ee-8a51-ecb59b355117

[crowdds]

Aah.  It fails every time if I use the "Convert to Issue" menu option on the Issues list.   But works if I use the "Move" menu option.