How often does this happen? Have you seen any pattern?

What were you doing at the time? Just surfing? Watching a clip? Reading an article? . . . . . .

Thank you for your reply, it looks like it appears randomly about every 20 min or so. I am usually looking for information, ordering stuff, reading email. so basically surfing. Also this probably started about 6 moths ago, not sure could be longer. I do update firefox often and have the latest version installed.

It actually just did it when I pressed the post reply button, nothing happened and the was a spinning wheel for about 30 secs and then it posted the reply.

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

https://support.mozilla.org/en-US/kb/firefox-takes-long-time-start-up