Example (see screenshot):
Starting point is a screen with widgets having mouse over state e.g. Table-Rows.
If you overlay these widgets e.g. with a flyout or a dialog and move the mouse over these overlaying cells/widgets, then the mouse over state change is still triggered for the underlying widgets, which does not correspond to normal UI behaviour.
Attached Screen-Example: The blue table-row in background is in Mouse-Over state and changes, as the mouse cursor is moved up/down across the table.
this is a known bug. It's already on our list. I will keep you updated on the progress.