Error when printing map title with ol-ext print dialog Openlayers

I’m using the ol-ext print dialog to enable printing with Openlayers. There was no option to type the map title.

So I added the code:

// Add a title control
map.addControl(new ol.control.CanvasTitle({ 
  title: 'my title', 
  visible: false,
  style: new ol.style.Style({ text: new ol.style.Text({ font: '20px "Lucida Grande",Verdana,Geneva,Lucida,Arial,Helvetica,sans-serif'}) })
}));

After this update, I was no longer able to generate PDF and it shows the error:”Can’t save map canvas…”

Complete code follows.

// Print control
var printControl = new ol.control.PrintDialog({ 
});
printControl.setSize('A4');
map.addControl(printControl);

/* On print > save image file */
printControl.on(['print', 'error'], function(e) {
  // Print success
  if (e.image) {
    if (e.pdf) {
      // Export pdf using the print info
      var pdf = new jsPDF({
        orientation: e.print.orientation,
        unit: e.print.unit,
        format: e.print.size
      });
      pdf.addImage(e.image, 'JPEG', e.print.position[0], e.print.position[0], e.print.imageWidth, e.print.imageHeight);
      pdf.save(e.print.legend ? 'legend.pdf' : 'map.pdf');
    } else  {
      // Save image as file
      e.canvas.toBlob(function(blob) {
        var name = (e.print.legend ? 'legend.' : 'map.')+e.imageType.replace('image/','');
        saveAs(blob, name);
      }, e.imageType, e.quality);
    }
  } else {
    console.warn('No canvas to export');
  }
});

Does anyone know what it could be?

// Add a title control
map.addControl(new ol.control.CanvasTitle({ 
  title: 'my title', 
  visible: false,
  style: new ol.style.Style({ text: new ol.style.Text({ font: '20px "Lucida Grande",Verdana,Geneva,Lucida,Arial,Helvetica,sans-serif'}) })
}));