I have had my laptop for years, and I have used firefox for years. Roughly, in the last 2-4 months, all the sudden, opening up new youtube webpages, tabs, videos, takes a while, 5-20sec to fully load a new page, and when I open a new youtube tab, my laptop fan starts spinning loudly, for ~20-30seconds. Once the page is loaded its fine again. Basically opening up a youtube page is slow, and its acting like its same as playing a modern video game on my computer which is ridiculous. I have edge installed, although I rarely use it, and it does not have this problem at all, its fast, and laptop fan does not spin.