signTextJS not working with Firefox 50.0beta10 about signtextjs HOT 4 CLOSED

function asyncDetermineUsages(cert) {
  let promises = [];
  let now = Date.now() / 1000;
  let certdb = Cc["@mozilla.org/security/x509certdb;1"]
                 .getService(Ci.nsIX509CertDB);
  Object.keys(certificateUsages).forEach(usageString => {
    promises.push(new Promise((resolve, reject) => {
      let usage = certificateUsages[usageString];
      certdb.asyncVerifyCertAtTime(cert, usage, 0, null, now,
        (aPRErrorCode, aVerifiedChain, aHasEVPolicy) => {
          resolve({ usageString: usageString, errorCode: aPRErrorCode });
        });
    }));
  });
  Promise.all(promises).then(displayUsages);
}