code: function(evt) {
    if (evt.dragging) {
      return;
    }
    /** @type {string} */
    let helpMsg = 'Click to start drawing';
  
    if (sketch) {
      const geom = sketch.getGeometry();
      if (geom instanceof Polygon) {
        helpMsg = continuePolygonMsg;
      } else if (geom instanceof LineString) {
        helpMsg = continueLineMsg;
      }
    }
  
    helpTooltipElement.innerHTML = helpMsg;
    helpTooltip.setPosition(evt.coordinate);
  
    helpTooltipElement.classList.remove('hidden');
  }
docs: Handle pointer move.
  @param {import("../src/ol/MapBrowserEvent").default} evt The event.