Preview FCEs moved in DRAFT dont works

[supercaccia]

TYPO3 v8,v10 flux9-dev

In draft workspace create for example a page that contains an FCE, for example a 2 column grid with content inside it and publish it.
After, in DRAFT move for example the FCE in anoter page layout column.
At this point if you preview the page on the frontend the FCE has lost its contents. The problem is solved by publishing.
According to my analysis this happens because moving an FCE creates a version of the FCE record but not of its contents.
The versioned FCE refers to the colPos of the live records and not to the draft ones (which do not exist).

[joneppie]

Deleting and copying hidden elements also returns the following error:
Argument 1 passed to FluidTYPO3\Flux\Provider\AbstractProvider::getGrid() must be of the type array, null given, called in /var/www/typo3-10er/public/typo3conf/ext/flux/Classes/Integration/HookSubscribers/DataHandlerSubscriber.php on line 433

[cweiske]

@joneppie The problem with deleted elements is #1939, and can be solved with #1957.