title: Java plugin replacement for digital signatures
body: <p>We have a custom Java applet that performs certain tasks, like loading a PDF from local filesystem, signing it with certificates from system KeyStore/smart card etc. Such actions are not possible in regular HTML/JavaScript. Now that Java is being deprecated across browsers, we are looking for possibilities to replace the applet functionality. </p>
  
  <p>There is this <a href="https://www.w3.org/TR/WebCryptoAPI/" rel="nofollow noreferrer">Web Cryptography API</a>, but unfortunately the spec does not cover using system keystore. There is another spec for this, <a href="https://www.w3.org/TR/webcrypto-key-discovery/" rel="nofollow noreferrer">WebCrypto Key Discovery</a>, but I don't think it is currently supported by any browser.</p>
  
  <p>Mozilla had an <a href="https://developer.mozilla.org/en-US/docs/Archive/Mozilla/JavaScript_crypto" rel="nofollow noreferrer">API</a> that might be exactly what we need, but unfortunately it is deprecated now.</p>
  
  <p>So it looks like our only options are:</p>
  
  <ul>
  <li>Write a custom desktop GUI app</li>
  <li>Write a custom browser plugin</li>
  </ul>
  
  <p>Or is there some better solution? What do you suggest? I don't care if the solution would be only for Internet Explorer since most of our users use. </p>