---
title: "Form/ File storage"
manual: "Form"
version: "main"
permalink: "https://docs.typo3.org/permalink/typo3/cms-form:concepts-form-file-storages@main"
source: "I/Concepts/FormFileStorages/Index.rst"
rendered: "2026-09-19T16:47:20+00:00"
---

# Form/ File storage {#concepts-form-file-storages}

Form definitions can also be stored in and shipped with your own
extensions and backend users can then
embed your forms. Furthermore, you can configure that your form
definitions:

-   can be edited in the `form editor`,
-   can be deleted with the `form manager`.

By default, all these options are turned off because dynamic content inside an
extension - possibly version-controlled - is not a good idea. There is also no
ACL system available.

**File uploads** are saved in file mounts. They are handled
as FAL objects. The file mounts for file uploads can be configured.
When adding/ editing a file upload element, backend users can select the
storage for the uploads.

Add your extension path as an additional file mount for form definitions as follows:

```yaml
persistenceManager:
  allowedExtensionPaths:
    10: EXT:my_site_package/Resources/Private/Forms/
```

Allow backend users to **edit** forms stored in your extension as follows:

```yaml
persistenceManager:
  allowSaveToExtensionPaths: true
```

Allow backend users to **delete** forms stored in your extension as follows:

```yaml
persistenceManager:
  allowDeleteFromExtensionPaths: true
```

The following YAML shows the default file mount setup for file (and image) uploads.

```yaml
prototypes:
  standard:
    formElementsDefinition:
      FileUpload:
        formEditor:
          predefinedDefaults:
            properties:
              saveToFileMount: '1:/user_upload/'
          editors:
            400:
              selectOptions:
                10:
                  value: '1:/user_upload/'
                  label: '1:/user_upload/'
        properties:
          saveToFileMount: '1:/user_upload/'
      ImageUpload:
        formEditor:
          predefinedDefaults:
            properties:
              saveToFileMount: '1:/user_upload/'
          editors:
            400:
              selectOptions:
                10:
                  value: '1:/user_upload/'
                  label: '1:/user_upload/'
```