Virtualising an ElementList causes the CMS ElementArea to fail to render

[jules0x]

When trying to virtualise an ElementList, I've found that the CMS ElementArea for that page will no longer render once you save the virtual element.
The front-end does show the element successfully, but the elements on the page are no longer accessible in the CMS.

https://reactjs.org/docs/error-decoder.html/?invariant=31&args[]=object%20with%20keys%20%7B%7D&args[]=
Objects are not valid as a React child (found: object with keys {}).

SS 4.4.0
Elemental 4.1.1
Element Virtual 1.2.2

[jules0x]

Looks to be the protected provideBlockSchema() function on ElementVirtual.php

Overriding the function on my custom virtual element as below resolves the issue

    protected function provideBlockSchema()
    {
        $blockSchema = parent::provideBlockSchema();
        unset($blockSchema['content']);
        return $blockSchema;
    }