That would annoy me too, but I've never noticed it. My main laptop is a Core 2 Duo, so not a speed demon. Have you tried with extensions disabled and/or with a new profile?
Believe so. But either way if its extensions well that sucks because I only have like 2-3 and I want. Extensions shouldn't be written in a way that does that -- chrome and safari don't have this problem and I have about 12 chrome extensions.