I checked the page, and had no problem.

Use this link to check that your plugins are up-to-date. If any are listed as unknown or research, do not worry about them.

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

One of the add-ons was the problem. I will remember this next time. Thanks for the help.

Please post its name so others can be helped. Also, contact it's support site.

I jumped on the add-ons too early. I went back to the website with all add-ons disabled to check them one at a time until the browser froze, to verify which one was causing it. Firefox locked up with all add-ons disabled.

It seems to have something to do with either the time spent on the page or scrolling the page. When I first landed on the page the navigation buttons did not cause a lock-up. But, spending time on the page and scrolling down to the bottom of the page causes a freeze on the next attempt to use one of the buttons. Doing either one of those without the other does not cause a problem. In short, the conditions seem to be:

Landed on the page > 15 seconds ago AND scrolled to the bottom of the page.

Maybe I am overlooking something but if so, it is happening in the background because I cannot see any other common denominator between working and not working. JavaScript, maybe?

Now this is really weird. While typing this message in Notepad with Firefox parked on the web page, Firefox crashed and generated a crash report. I reopened Firefox; it is running in the background, parked on the page now. I am waiting to see if it crashes again.

There is another behavior that I am not sure I should blame on Firefox or not. If I leave a YouTube video paused and walk away from the computer long enough for it to go into sleep mode, when the computer wakes up, the entire browser page is white except for the video. That includes all the controls and links. I can tell by clicking the PLAY or PAUSE button (or where it should be) the button functions, even though I cannot see it. If I close Firefox and reopen it, it functions properly. It does not "go blank" every time. But it does do it frequently.

Waited 20 minutes -- twice as long as it took to crash awhile ago. No crash yet. I am going to go ahead and post this.

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Restart Firefox. Are there any problems?

Removed the hardware acceleration. Restarted Firefox. Same behavior.

I've called the big guys to help you. Good luck.