Finally, 2020 LTS offers a series of Editor changes for programmers and technical artists alike, to more efficiently set up workflows for the entire team.
These comprise Prefab support for AssetPostprocessor, a Unity Editor API that lets you hook into the import pipeline and run scripts before or after importing assets. If OnPostprocessPrefab is implemented, the postprocessor can modify the Prefab. All added objects are then flagged with DontSaveInEditor to prevent changes from being applied to the source Prefab.
The enhanced Prefab import also serves to increase correctness, performance, scalability, and cacheability, alongside other key attributes. Regarding script dependencies, Prefabs that contain MonoBehaviours will now sync directly with the script, so as not to lose references in the case of compile errors.
Then there’s the Hierarchy view, which will now display the updated version control status for Prefabs. Multiple Prefabs can even be dragged into the scene simultaneously, to help you create rapidly.
Source: Unity Technologies Blog