Generally I prefer to use Google Chrome's web browser. I have tried using IE and Firefox as well. It seems almost random as to when it happens. It seems to happen only when entering food into my daily log.
I have been reading on the forums all morning with no problems until I click on Foods. Sometimes it works, sometimes it doesn't.
It very well could be an AD that is causing this. That would explain its seemingly randomness. It has been happening for a few days for me.