WF's definition of Converted Issue Originator: A field in a project or task report that displays information about the user who is the Primary Contact of an issue when the issue is converted into a project or task. The field also displays in the Project Details section where it displays the name of the Primary Contact of the converted issue.
And then related to above, Primary Contact:
The Primary Contact is the creator of an issue and it is automatically designated by Workfront when the someone creates the issue. You can manually update this field if you have Manage permissions to the issue. An issue can have only one Primary Contact. If you change the Primary Contact, the user originally designated as the primary contact still has Manage access to the issue. When converting an issue to a task or a project, the user designated as the Primary Contact of the becomes the Converted Issue Originator of the project or task. If the Primary Contact of the issue is updated after the issue was converted, the Converted Issue Originator will be preserved as the Primary Contact of the issue at the moment when the conversion happened.
Bookmark this useful WF terminology glossary! https://experienceleague.adobe.com/docs/workfront/using/basics/workfront-terminology-glossary.html?lang=en
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