Fix crash if empty certificate is provided in PKI list

src/userconfigdlg.cpp

@@ -519,6 +519,10 @@ void UserConfigDialog::updatePKICertificateList() {
 	for (it = m_user.pkiCertificates.begin(); it != m_user.pkiCertificates.end(); ++it) {
 		PKICertificateEntry certificateData = *it;
 
+		// Don't attempt to load empty certificates
+		if (certificateData.second.size() < 1)
+			continue;
+
 		TQCString ssldata(certificateData.second);
 		ssldata[certificateData.second.size()] = 0;
 		ssldata.replace("-----BEGIN CERTIFICATE-----", "");