Having the same problem.  I also have the issue where I upload a PDF, it shows 100% but it stays gray and doesn't turn blue (hyperlink).  When you try and save the invoice/expense/bill etc you get the following message.  

"The file you’re attaching hasn’t finished uploading, or there was an error. Wait until it’s finished or dismiss any errors and try saving again."

Needless to say, this is extremely frustrating.  Its been an issue all week.  I have cleared the cache which makes zero difference.