Oh, that happened to me for a while. It was something about ads...I was having trouble typing in any kind of box, replying to a post, etc. Try rebooting, it did help me for a while. I tried a lot of things and found that an Amazon plug in was causing most of my trouble - I think it was some kind of plug in that monitors everything to add to your wish list? Once I nuked that - mostly nuked it, it's impossible to completely remove - things behaved better.