You can copy the value form some from a source field to some a destination field. Click the + Button to add additional field pairs to your configuration.
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Overwrite / Append / Prepend
For text fields and some field fields that can take multiple values (like checkboxes) you can choose to overwrite, append or prepend the new value to any existing value. In the case of text field, you can also choose a separator that will be put between the values (not shown in the screen shot above).
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If the destination field is 'Fix Version/s', 'Affects Version/s' or some custom field of type 'Version Picker', you can choose that a new version will be created in the target project, if does not yet existexisted. If you don't choose this option and that version does not yet exist, the user will get an error message and the transition won't complete.
However be aware, that the version will be created, even if the user does not has have the 'Administer Projects' permission. (Normally a user needs that permission to be able to create a new version.)
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