3861056 created the issue

When I select multiple files and copy them between two browser windows, it does not work. After one or two it just hangs, while continuing to display that it is copying the first file that it started on (I think). This worked seamlessly in the previous version.

A work around is to copy one file at a time (via drag & drop) to the other browser window.

This does not seem to be a problem with the down load part, as I can download multiple selected files to my Macbook. It seems the upload portion is more affected as ... when I select muliple files to on my macbook and upload them to a site I get a similar problem.