Steps

1. Use Ibexa 4.6.9
2. Create content type with the field ImageAsset
3. Create a content item of a new content type
4. Upload an image to the ImageAsset field
5. Click edit image on the uploaded image
6. Click Save
7. Click Save as new or Apply changes to all

Actual result
The image is not saved and an error is thrown:
An error has occurred resolving the options of the form "Ibexa\ContentForms\Form\Type\Content\ContentFieldType": The required option "struct" is missing.

Expected result
The edited image is saved.