FEATURE: Iframe error handling with proper user feedback

[laurahaenel]

Feature Request

Description

When an error inside the iframe occures, the user has no other possibility than reloading the whole page.
For proper error messages, a modal dialog would appear that contains the error message and two button.
Button 1: Reload (will reload the iframe content)
Button 2: Close (close modal dialog)

The iframe currently directly prints fusion errors.

Is this something that adds value to neos? 😅