I found it! The function call shall be

togglecolumn(parent.frame1.togglecol)

and the object reference in the function shall be the
same as in the case that the id-element is in the same
frame as the function, i.e the function will be

function togglecolumn(column_id) {
	if (column_id.style.visibility=="hidden") {
            column_id.style.visibility="visible";
        }
		else {
            column_id.style.visibility="hidden";
        }
}

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