I lived with this until a few days ago.
Then I had to re-boot my wireless router for an unrelated reason. When it finished re-booting, FR was quite a lot faster.
I then cleared my cache (temporary internet and website files, also cookies and website data).
However, that had no effect that I could perceive.
But rebooting the router definitely helped.
Yeah, FR is slow as heck for me most of time. More specifically, FR is slow to START LOADING a page. When I click on a FR link, I will get that spinning wheel for a long time, then once it starts loading it usually goes pretty fast.