Printing doesn't work in Chrome 77 with client rendering

In Chrome 77 the behavior changed so that PDFs with auto-print enabled that are embedded in a web page no longer trigger the print dialog https://pdfium.googlesource.com/pdfium.git/+/2021804f1b414c97667c03d7ab19daf66f6a19ef

By default WebViewer has taken this approach in Chrome for printing when using client rendering since version 2.2.1, which is why you may see issues trying to print in Chrome.

WebViewer versions 5.2.5 and higher contain a fix for this issue. If you update to the latest version this problem will be fixed. Download the latest version here.

Note that the fix is only applied to the default UI. If you're using the legacy UI or unable to update to the latest WebViewer version please use the workaround below.

Call the instance.useEmbeddedPrint(false) function after WebViewer is ready.

In versions 5.1+

WebViewer({
  //...
}, viewerElement).then(instance => {
  instance.useEmbeddedPrint(false);
});

In versions 4.x or 5.0

const myWebViewer = new PDFTron.WebViewer({
  // ...
}, viewerElement);

viewerElement.addEventListener('ready', () => {
  myWebViewer.getInstance().useEmbeddedPrint(false);
});

Inside a config file

window.isPDFiumSupported = function() { 
  return Promise.resolve(false);
};

Outside a config file

var myWebViewer = new PDFTron.WebViewer({
  //...
}, viewerElement);

$(viewerElement).on('ready', function() {
  var iframeWindow = viewerElement.querySelector('iframe').contentWindow;
  iframeWindow.isPDFiumSupported = function() { 
    return Promise.resolve(false);
  };
});