But none of those things will ever really bottleneck the browser except for maybe the PDF viewer. The performance of bookmarks, tab management, search, and basically all your other examples doesn&#x27;t matter. The parts of the browser that benefit from speed are written in C++.<p>Not that I&#x27;m convinced simply compiling with ICC will actually have a noticeable impact on the day-to-day performance of the browser, but it might speed up layout and other specific CPU-bound tasks. I&#x27;d love to see some benchmarks, but I think it&#x27;s silly to shrug it off by saying that it won&#x27;t matter because the browser UI is written in JavaScript.