# Auto

> The width of the dropdown matches the width of the provided Rect, but if the content is wider, it expands to fit the content. This is the only supported mode for OS menus.

## Definition

* **Type:** Field
* **Namespace:** [UnityEngine.UIElements](/engine/6000.5/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
Auto = 0
```