# undo

### Description

@short: Enables the Undo functionality for the gantt

@signature: undo: boolean

### Example

~~~jsx
gantt.config.undo = true;
~~~

**Default value:** true

### Related samples
- [Undo/Redo changes in Gantt](https://docs.dhtmlx.com/gantt/samples/02_extensions/14_undo.html)

### Details

:::note
This option is defined in the **undo** extension, so you need to enable the [undo](guides/extensions-list.md#undo) plugin. Read the details in the [Undo/Redo Functionality](guides/undo-redo.md) article. 
:::

### Related API
- [redo](api/config/redo.md)
- [undo_actions](api/config/undo_actions.md)
- [undo_steps](api/config/undo_steps.md)
- [undo_types](api/config/undo_types.md)

### Related Guides
- [Undo/Redo Functionality](guides/undo-redo.md)

### Change log
- added in version 4.0