Just found this thread and am relieved (sort of) to see others having the same problem. I thought it was Firefox or my computer, but when I started seeing this on Chrome I grew suspicious. For me, after being on FT for ~15 min or so, I notice a firefox.exe process gobbling up 5-6 GB of memory, and everything slows to a crawl. After I kill this process in the Task Manager, everything is OK again. Similar symptoms on Chrome. Only seems to happen on FT. I have not tried an ad blocker or disabling infinite scroll.
Edit to add: now tried disabling infinite scroll; seems to help
Last edited by mangoMan; Apr 25, 2018 at 1:24 pm