Decorators and FormPreview doesn't work anymore since 6659.
|Reported by:||Owned by:||nobody|
|Has patch:||no||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
The fix from changeset 6659 leads to an error if you combine a FormPreview with a decorator, because FormPreview (as a class) doesn't has a