There are two things I can think of that may be causing problems. If you have infinite scroll turned on, you may find that the page slows to a crawl as it loads more and more pages. That feature can be disabled in the settings. I found that disabling infinite scroll freed up a lot of my computers resources.

Secondly, it may be an ad problem. Users are reporting that the new FT is sending a ton of server requests to support all the ads running on the page (See this post). There are some ways to solve this problem, but they involve browser addons that will stop advertisements from appearing.