Child GameObjects
While you normally want a locked Prefab to be shown as one object, it is possible to reveal important children GameObjects that – for some reason – need to stay visible and editable.
When revealed, they appear in the Hierarchy as they normally would:

If the revealed child is not a direct child of the root, its direct parent and other ancestors will also appear, but they will be shown as disabled (unless they are also intentionally set to be revealed):

Revealing child GameObjects
To reveal a child GameObject, you can do it in two ways:
On the BlackBox component
Click on the Show Revealable Items button on the BlackBox, and expand the foldouts until you arrive to the GameObject or component you're interested in.
Child GameObjects are preceded by a small [GO] icon:

Press the [+] button to add the GameObject to the reveal list.
Via the context menu
Child GameObjects can also be revealed in context.
In the Hierarchy, select a child, right-click and choose BlackBox > Child GameObject > Reveal in the xxx list. Revealing a child GO this way will reveal it using its Transform.
Alternatively, you can right-click any component in the Inspector and choose BlackBox > Child GameObject > Reveal using this component in the xxx list. Revealing it this way will use the component that was right-click (see below).
Which components are displayed?
When revealing GameObjects, you can choose which component(s) to reveal the child with. Revealed components are visible and editable, but the other components aren't.
For instance, a child GameObject revealed with its Transform will only show the Transform when inspected. If that object is revealed using its BoxCollider, then it will only show that and not the Transform.

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