I have a CKFinder UI in a ColdFusion application to manage file uploads. In migrating our application to AWS, and preparing it for running it in an array of load balanced servers, we moved the file repository from a folder local to the application to an S3 server. The only change made to the configuration was in setting the base path to the S3 server, which is mapped to our servers as a remote drive using TNTDrive.
The change works fine in Chrome, but after uploading the file in Firefox, we get the following error thrown by CKFinder: 'Unparseable date ""'. The file is uploaded as expected, so my first thought was that the date display for the file was not working for Firefox. We had the file display include the filename, date of upload, and file size. I disabled the date display and still get the error. Additionally, refreshing the page does not make this error go away, but navigating to another page and returning does, with the uploaded file displaying correctly.
One additional thought I had that might provide a clue is that S3 runs in UT and we have our servers set for Mountain Time. Perhaps this is something Firefox is particularly sensitive to? This is a legacy of our previous server that we do intend to remedy in the near future (we have a number of features that are dependent on MT).