Random Firefox process is using 25% of my CPU

Pretty much as the title says, going into task manager I see a Firefox process constantly using around ~25% of my CPU at all times as shown by the attached photo; The CPU is a quad-core 3.2Ghz i5 3330, Ending the task means that the process stops without causing any changes to Firefox, no tabs close or videos crash which only makes me wonder to what it's used for and why is it hogging my CPU.

Thanks in Advance, Deinsti