I just spent quite some time preparing a message for this forum and I think it was discarded without posting. I will try again, but request that the admins please look into it.
Thanks for letting us know BillM. I have moved this message to the community suggestions area for discussion. The only cause I can think of is if the browser timed out due to the amount of time you spent with the window open. We will look into it to see if we can find a cause. Can you send me a private message with your specifics (browser, computer OS and steps to reproduce)? In the meantime, please let us know if it happens again.