Hi Robert, What you're experiencing is not normal behaviour. First, let's try refreshing Firefox. This will purge a lot of your Firefox files, while retaining most of your personal data. For instructions, check out the following article: Refresh Firefox - reset add-ons and settings

Thank you, Chris -- I did the reset, however, it did not help. I then removed Firefox completely, did a restart, and downloaded it again. So far it seems to be working much better. I will let others know in a few days. Thank you!