TYPO3 Core

If the sorting of a parent record is changed the move method in TCEMain is also called for all its child records (inline elements) recursivly. But for the child records the destination pid is the current page id, so the sorting of the childs is changed to be the first item on page. This is not the expected behaviour and also results in very bad performance. This can be disabled in TCA by the behaviour flag disableMovingChildrenWithParent but this also disables real moving to other pages.
On sorting the moving of childs should be disabled, since it does not make sense here.