I just gave it a try in a current, Firefox-not-being-sluggish state, and it seems it may be a bit hard to correlate profiler lines to exact tabs. (For example, 7 of the top 13 rows that had domains associated were Google-API-related, but I don't think they're being used from Google pages...) Still, when I next enter a laggy state perhaps this will help finger the culprit(s) unambiguously. Thanks!