This page shows what fields and custom fields are supported in Issue Merger app.
Difference between Replace and Append
Replace removes the old value and save a value taken from the source issue. Append adds selection to existing value (if possible).
System fields
Name
Type
Assignee
Custom fields
Jira Software
Jira Service Management
Also, there are two options in the connected with Jira Service Management:
Merge comments into public
Add reporter to the participants list
Rank
Story points
Satisfaction date
Time to first response
Time to resolution
Request Participants
Append and Replace
Customer Request Type
Attachments
Append
Comments
Append
Description
Specified format
Due date
Issue links
Labels
Append and Replace
Priority
Reporter
Security
Subtasks
Summary
Votes
Append and Replace
Watchers
Append and Replace
Worklog
Name or type
Radio buttons
Single, Multi and Checkbox Select
Single and Multiline text field
Name
Epic color
Epic link
Epic name
Epic status
Development
Name
Approvals
Approvers
Customer Request Type
Organizations
Request
Sprint
Satisfaction