PDF.js Express Viewer Watermarks

Hi everyone,

There was been many posts recently about watermarks appearing on the PDF.js Express Viewer product, even with a license key.

Please make sure to follow these debugging steps before creating a ticket:

  • Make sure you are using the npm package @pdftron/pdfjs-express-viewer and not @pdftron/pdfjs-express
  • The watermark will always appear on localhost. It only gets removed in production environments
  • If you recently switched from @pdftron/pdfjs-express to @pdftron/pdfjs-express-viewer, make sure the static assets in /public get properly copied over. We recommend deleting the old assets and completely replacing them


Hi, can you kindly check on our account? It did not have watermarks before but when we changed our domain, the watermarks showed. Thanks