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# UI extensions - Web app tools

> Instructions to build and manage UI Extension with Contentful web app tools | Creating and Deleting a UI Extension

> **Info**
>
> **Use the [App Framework](/extensibility/app-framework) for any new projects.** We recommend creating apps instead of UI extensions. [Read the app FAQ to learn why](https://www.contentful.com/help/contentful-app-framework-faq/).

### Editing a UI Extension

Navigate to **Settings > Extensions** in the Contentful web app. In the **Extensions** page:

1. Select **Edit** corresponding to the desired Extension to be edited.

![Edit extension](https://fdr-prod-docs-files-public.s3.us-east-1.amazonaws.com/contentful.docs.buildwithfern.com/5ff2f716d769866b76806e169cd26bb12808d8065217d2da07fa129da0da83e8/docs/assets/images/edit-delete-extension.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6KXJSKKNFOCF7G4B%2F20260930%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20260930T001030Z&X-Amz-Expires=604800&X-Amz-Signature=caf26185e402cd5173b559120a7644f7adc0701e3a978057cda9a5d1c153d040&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)

2. Perform the required changes and **Save** the updates.

## Deleting a UI Extension

In the **Extensions** page:

1. Select **Delete** corresponding to the desired Extension to be deleted.

![Delete extension](https://fdr-prod-docs-files-public.s3.us-east-1.amazonaws.com/contentful.docs.buildwithfern.com/5ff2f716d769866b76806e169cd26bb12808d8065217d2da07fa129da0da83e8/docs/assets/images/edit-delete-extension.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6KXJSKKNFOCF7G4B%2F20260930%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20260930T001030Z&X-Amz-Expires=604800&X-Amz-Signature=caf26185e402cd5173b559120a7644f7adc0701e3a978057cda9a5d1c153d040&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)

> **Info**
>
> Deleting the Extension would restore the default settings (Appearance) on all the fields to which this Extension was assigned.

2. Confirm the deletion by clicking **Delete** in the dialog box.

## Next steps

* [Refer to the UI Extension SDK reference guide for more technical details.](/extensibility/app-framework/sdk/)