Today, for the first time, I noticed a process named "Web Content". I was running top because firefox was once again not allowing me to scroll. Having been down this road before, I would normally have just closed and reopened firefox. I needed to do it fairly often. Web Content was new. Eventually, I discovered "electrolysis" (why that name?) and the schedule: https://wiki.mozilla.org/Electrolysis#Schedule_and_Status , but I'm not sure how to read it. What the heck is "riding trains"? My firefox is 52.2.0 64-bit. yum.log says it was last updated on the 16th.
As is unusual, I had a pretty good idea which tabs were using up the CPU, so getting scrolling back was not too hard, but my usual close and reopen did not work. Is this a new "feature" of firefox? Will close and reopen consistently fail to resolve CPU-burning issues? Will I have to go on a tab-hunt every time?