I used PDF.js in a side project for comparing pdfs and it worked quite well. It runs completely client side, so I can build the site with a static site generato

I used PDF.js in a side project for comparing pdfs and it worked quite well. It runs completely client side, so I can build the site with a static site generator and html: https://www.parepdf.com/ https://www.parepdf.com/ It can start to bog down with large image heavy pdfs. But overall it runs performantly.