Height of parent node at cursor position

I am trying to build a custom editor. I want the menu to follow the cursor. The menu should be always below the cursor. So I need some heights. Currently I have the menu moving along with the cursor:

let selection = this.editor.state.selection;
if (selection.empty) { // cursor
  top = this.editor.coordsAtPos(selection.head).top - this.wrapper.getBoundingClientRect().top;
  this.menu.style.top = top + 'px';

This is working great, but I need to add the height of the selection to top. But I can’t find a way to get the height of a node, because as I understand the nodes aren’t referenced to the dom nodes, to get the height of that.

@marijn isn’t it possible to add width and height to the return value of coordsAtPos?

Ok, figured it out, bottom which returns from coordsAtPos is measured from the top and not from the bottom. So I have to use that one.