Session timeout is not apparent

When your session times out, often you will not receive a message as such. When you attempt to do certain operations, such as create a new data set, or refresh a dataset... it will pause for a moment and appear to be working then bring you either to a blinking ui or the previous view you had. 

The only way (that I found) to find out that you are actually no longer logged in is to click the refresh button. Then it will pop up on refresh that you must authenticate. 

This can be confusing. Perhaps make it obvious that you are getting logged off somehow by prompting to stay logged in?