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How to generate the email details in workitem in RPE?

Accepted answer

If you want to print creator's email address, you can directly print it by adding workitem/workItem/creator query. workitem/workItem/creator/emailAddress will provide the email address.
To get the details of all contributers, you can workitem/contributor query and get the details. You can have an JavaScript array to hold details (workitem/contributor/uniqueId, workitem/contributor/emailAddress) so that you can read email address from the array.