Steps:
1. Open attached "TestPackage" package
2. Open Scene17
3. Drag and drop Capsule10 GameObject to the Project Browser
4. Choose "Original Prefab"
==>
Duplicate identifier 1672280479522650189.
GameObject became "missing asset" prefab instance. Prefab asset is broken.

Option2:
1. Add Cube to Hierarchy and convert it to prefab
2. Save scene "Test1"
3. Save this scene as "Test2" as well
4. Open both scene (multiscene setup)
5. Drag Cube prefab instance from "Test1" under Cube prefab instance in "Test2"
6. Drag to project browser root Cube prefab instance
7. Choose "Original prefab" in confirmation dialog
==>
Duplicate identifier 1672280479522650189.
GameObject became "missing asset" prefab instance. Prefab asset is broken.

Take a look into attached movie for details

Also reproducible in 2020.3.23f1