Ever make changes to a Prefab in your Hierarchy and click in the Inspector under Overrides > Apply and nothing happens? That’s because your Prefab has at least one reference to something outside of the Prefab itself. Simply move these referenced objects/scripts inside the prefab (or delete the references to things outside of the Prefab…
Are you using Universal Rendering Pipeline (URP) and some prefab previews in your Project > Assets folders are black, missing (shown as blue cubes) or not reflecting changes you made to prefabs? Just right-click on one or more prefabs and select Reimport and wait a couple seconds. If the preview images are still black, missing…
Click the 3 dot menu in the upper-right corner of any GameObject in the Inspector and click Debug: Afterwards you can see a lot more information about your scripts, including private variables: Alternately, if you have the amazing NaughtyAttributes package in your project, you can use [ShowNonSerializedField] attribute: [ShowNonSerializedField]private float myHiddenVariable = 1f;