I agree that it might be OS X related. I switched from Chrome to Firefox about a year ago, while I was still using Mac. I did notice a minor performance drop, t

I agree that it might be OS X related. I switched from Chrome to Firefox about a year ago, while I was still using Mac. I did notice a minor performance drop, though not enough to be too upset about. Since December I've been using Linux full time and haven't noticed any lack of performance from Firefox. I tried Chromium about a month ago to see how it would hold up, and didn't notice any performance boost over Firefox. Granted, I am also using different machine with similar but newer processor and (integrated) graphics hardware, I am using a several-versions newer Firefox than I was last year (I was running v27 nightlies at the time and now I run v29 stable). Still I think that some performance drop in Firefox on OS X might be attributable to a lower-performing graphical backend.