First the comment "so remove it from the mesh" is wrong / missleading as
since 034c27ab78 the delete in that if is
not in there anymore.
Second the m.nodes map is not updated so setting `diff = true` will call `applyTopology` without any changes... which seams useless.
Third the rest of the code already checks for Ready so this special case
here should not be needed.
81f592de74