Layout library redraw changing string size help

I believe if you give the element a background colour, it should get cleared properly:

var Layout = require("Layout");
var clockLayout = new Layout( {
      type:"txt", font:"15%", label:"Hello World", id:"clock", bgCol:g.theme.bg
    });

const utils = {
  random_element: function(array) {
  return array[Math.floor(Math.random() * array.length)];}
};

const words = {
  approx: ['\'Bout', 'About', 'Around', `Summat\nlike`, 'Near', 'Close to'],
};

function draw() {
  clockLayout.clear();
  clockLayout.clock.label = utils.random_element(words.approx) + "\nHalf past\nnine";
  clockLayout.render();
}
g.clear();
// can put draw(); here
Bangle.setUI("clock");  // Show launcher when middle button pressed
Bangle.loadWidgets();
Bangle.drawWidgets();
draw();
Bangle.on('touch', function(button, xy) {
    if (button == 1);
    else{
      draw();
    }
  });