If you have duplicate cases or cases that you want to merge into a
single case, you can now merge two or three cases into one master record. When you merge
cases, the master record is updated with your chosen field values. Most related lists, feed
items, and child records are merged into the master record. The master record keeps the
Chatter feeds, your values for read-only and hidden fields (except Created Date and Created
By), related items, and security.
Where: This change applies to Lightning Experience in Essentials, Professional,
Enterprise, Performance, Unlimited, and Developer editions.
How: To turn on Merge Cases, from Setup, in the Quick Find box, enter
Support Settings, and then select Support
Settings. Select Enable Case Merge (Beta).
In a Cases list view, select two or three cases, and click Merge
Cases. You can merge cases from custom list views as well. You can’t
merge from the Recently Viewed list, but you can merge from the Recently Viewed Cases
You can also start a merge from within a case and add the other cases to merge.
Select the field values to merge into the master.