Firefox is slow on my computer even if neither my RAM nor CPU is sonsumed. I made tests while using less than 20% of each. When I talk about "being slow" I mean that even my pointer is slow. It lags and blinks from one part of the screen to another one, just as if I moved it but without displaying any animation. It seems some sort of frame skipping but I don't really know if that is the reason. This applies to everything, not just my pointer. If something else runs on my computer - let's say a VoIP chat - that said chat has the same issue: audio packages are not played until the pointer starts moving again. If I try to write something on a forum or in a firefox page, the text I write is not displayed as I write it but, much like the pointer, few frames after I write it and every letter I wrote is displayed at the same time. Everything only happens when Firefox is the active window. If it runs in background everything goes smoothly. If not for that Firefox runs pretty well. It doesn't crash, it loads pages, it plays videos etc. However having everything running slower than usual is quite annoying.