Issue Summary

Environment

n/a

Steps to Reproduce

1. Create a project with a user custom field
2. Create a CSV file that has a column for that custom field
3. Populate the user custom field column in the CSV file with either valid account IDs or valid email addresses
4. Import the CSV file using External System Import, and map the custom field column to the correct custom field in Jira

Expected Results

The file is imported, and the custom field is populate with the correct users for the new issues.

Actual Results

The import fails, because the users could not be created that were referenced in the custom field column.

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Notes

Related to https://ecosystem.atlassian.net/browse/ACJIRA-1751

Workaround

Specifying custom user fields by username is still supported in the short term.