@andrew84 Yes! That's more or less the issue I was having! The clipboard wasn't appearing for me to select the files. I do have auto hide sidebar on but I've always had it on. The issue only started a few weeks ago. However like I said, It wouldn't be permanent and if refresh the page or navigate away and return to try again, it would be fine. This is how I found a solution I posted above this post to Leo - when I was able to select a file from clipboard I'd select "don't show this pop up again" and now I'm able to select files from the folder popup instead. Thanks for this.
