On Mon, 13 Aug 2018 16:05:44 +0100, "J. P. Gilliver (John)"
wrote:

In message ,
writes:
[]
wrote:
This started yesterday. Firefox hangs, using 50-60% CPU and no network
activity. I restored the C drive and MBR from a week ago (Aconis
image) and it got better for a little while but it was back. Then I
tried refreshing Firefox, same thing, OK for a while then it started
slowing down again. There is no particular page activity.
[]
it and it works OK again. It really just seems to be bad on things
that are highly ad supported like Facebook or a boat forum I look at.
I think you are right about an ad bot.
I am going to turn on that connection monitor in FF and see if I can
find the culprit.

At first you said "no particular page activity", now "It really just
seems to be bad on ..." (-:.

When it _is_ "bad", _is_ there network activity? (I use Bitmeter2
[http://codebox.org.uk/pages/bitmeter2] for its small semi-transparent
window, and the fact that it shows incoming and outgoing in different
colours - but there are plenty similar, and even the one in Task
Manager's Networking tab will show activity.)

Task manager says the network is not going. That was the first thing I
looked at. CPU is running about 60% and pretty much all of it is
Firefox