I don't know what these commenters are talking about. I've been using FF on Mac for over a year now on 3 different Mac Machines. It's super fast, as good as Chrome. May be you need to reset it or something to get it working properly. The only issue I had with FF is Developer Tools, which are also have improved a lot with latest release, and continuing to improve.
As I noted, the issue affects many, but not all, Mac users. It seems to be a special configuration of display resolution and other factors that can be difficult to replicate. That’s great for you that it’s working, but you shouldn’t discredit this very serious problem for the general user base.
Sorry, it came of stronger than I wanted to. I actually run into high CPU utilization shortly after I posted it. Haven't had it for a full year, may be something in later version got messed up. I did go away after refreshing FF though, so I do recommend trying it to see if it will fix things. I am routing for FF, but it's definitely not perfect.
