I would like to be able to create a custom field similar to the external release date field so I can track by month, quarter, date, etc in the idea module. It would help planing and reporting the ideas that we are committed to work on, but they are not at the feature stage yet.
Thank you for the request.
At this time, we do not have plans for custom fields relating to specific fields on other objects. However, we do have the ability to link records with one another across the entire application. You can access this via the Actions menu on an Idea and you can link it to a release. This would then give you one-click access to the external release date.
While we understand that this isn't exactly your specific request, we hope it can help.