There is no message after this happens. It works fine as long as I'm on it, but when I step away for any length of time, it shuts itself down. I'm on a laptop, and I do not close the top, but when I do so at night with FF open, it is shut down when I reopen it in the morning, which has never been the case before v. 47. Since I usually keep about 30 tabs open at all times, it's most annoying, because it takes so long to start back up. It also does this in safe mode. I refreshed FF not long ago, and it's been nothing but problems ever since. Will doing a complete uninstall and deleting all profiles help? I used FEBE to restore my profile and add-ons before, but wasn't really satisfied with it. Seems FF has not been notifying me of available add-on updates or updating automatically, so I had to completely reinstall a few, since the old version didn't work with the FF version. TIA for any help you can give me.