Can the Calc drag/fill handle be hidden?

I have a person who says the drag handle (the black dot on the lower right corner of a cell or a selection, just to make it clear) did not appear on LibreOffice 5.2.5 and started appearing after he performed a not-very-clear operation. I assume that the drag handle is an essential element of Calc , that should always appear and there is no option to hide it. If it doesn’t appear, it is probably a bug, isn’t it?

Probably a bug, Don’t see it reported. But, it is repeatable?

It is normal that the fill handle (that’s what LibreOffice calls it) hides when you are entering/editing content in a cell or in the Imput line (aka formula bar).