Wally4u Ok i did some testing;
When not reading a novel, firefox takes 0.6% of my cpu.
When reading a single chapter, firefox takes 4% of my cpu.
When consecutively scrolled 10 chapters, firefox takes 6% of my cpu.
When consecutively scrolled 20 chapters, firefox takes 8% of my cpu.
When consecutively scrolled 40 chapters, firefox takes 9% of my cpu.