Struct that represents a stage handle.
A stage is an editing context which includes a collection of Scenes. The main stage contains all the currently open regular Scenes, while a Prefab stage contains a preview Scene used solely for editing the Prefab in.
The breadcrumbs which are shown in the Scene view when in Prefab Mode each represent a stage.
| Contains | Does the stage contain the given GameObject? |
| FindComponentOfType | Returns the first active loaded object of the given type. |
| FindComponentsOfType | Returns a list of all active loaded objects of the given type. |
| IsValid | Is this stage handle valid? |