Hi vkulkarni, unfortunately, it appears this feature is not implemented in the viewer yet. Firefox uses a JavaScript library called pdf.js and when I look on the issues list for pdf.js, I see a couple open threads about digital signatures: * https://github.com/mozilla/pdf.js/issues/4743 * https://github.com/mozilla/pdf.js/issues/1076 Once a fix is eventually made in pdf.js, it should make its way into Firefox a version or two or three later. However, at this point, I don't have a timeframe for when this might be supported.