Reproduction steps (simplified, see the History for the original repro steps):
1. Create Prefab A and Prefab B
2. Open Prefab A in Prefab Mode and add Prefab B as child
3. Add a component to Prefab B (so it will be an Added Component in Prefab A)
4. Delete Prefab B from the Project folder
5. Go out of Prefab Mode, and open Prefab A again in Prefab Mode
6. Replace the missing Prefab by any Prefab
7. Observe the crash

Reproducible with: 2022.3.5f1, 2023.1.4f1, 2023.2.0a23
Could not test with: 2021.3.28f1 (Cannot perform step 4 due to error “Prefab instance problem”)

Reproduced on: Windows 10 Pro

First few lines of the stack trace:
{\{0x00007ff6d71bf48c (Unity) MergePrefabChanges }}
{\{0x00007ff6d71a18dd (Unity) MergePrefabInternal }}
{\{0x00007ff6d71a0269 (Unity) MergePrefab }}
{\{0x00007ff6d71a0586 (Unity) MergePrefabInstance }}
{{0x00007ff6d71a045c (Unity) MergePrefabInstance}}