I had no problem with those links. Please describe the problem in detail. What happens when you try? Error messages?

Thanks for the reply. For instance on accuweather.com it likes to slow down and get unresponsive. And weather.com doesn't load it all with any info. You can see a spinning sign over a blue window on the left side. Also Staples.com also slows down and finally reports, 'a script is busy and slowing you down.'

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options) key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?

Start your Computer in safe mode with networking. Then start Firefox. Try Safe websites. Is the problem still there?

Starting The Computer In Safe Mode;
Free Online Encyclopedia

Thanks again, FredMcD. Much better! Didn't have any of those problems. Those websites acted smoothly.

What made the problem go away, computer or Firefox in Safe Mode?

Sorry I didn't explain. You had suggested the Safe Mode, which I did. So the Safe mode loads the program differently...

Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If the problem goes away, that tells us one thing. If it does not, that tells us something else.

When a computer is started in Safe Mode, only system programs are running.

I suppose I need to play with settings now, eliminate one at a time, to see what is causing the problem.

Maybe: Bitdefender QuickScan