This PR introduces a new option parameter fallbackParent. It allows you to be more flexible with determining where the fallback ghost element gets appended. You can either pass a DOM node or a function that retrieves the dom node.

Right now you can choose fallbackOnBody and it will use the body, but with this change you have a lot more power in determining what the parent needs to be of the fallback ghost. It's not always feasible to append things to the body.

The fallbackOnBody is still supported, but marked as obsolete and removed from the docs.