Do you see this problem exhibited on a large majority of sites? Some websites use a redirection technique to keep you on the same page. Firefox detects these scenarios in most cases and prevents it from happening. If this is happening often, the issue may be else where. I assume you hae attempted the standard Safe Mode and/or used the Reset Firefox features?

Thank you for your suggestions. However, this does not occur on most sites. I am aware of the redirection capture-and-hold insanity by the designers of some websites. (Why would anyone make a purchase from a company that tries that unethical ploy?) This problem isn't the same. I simply need two clicks of the back button to navigate from any web page to the previous web page when on nbcnews.com when I use FireFox. Although I have a somewhat more than basic knowledge of html, php, javascript, etc., I cannot find anything in the page source that may cause this. Thanks, again.

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

• Do not click the Reset button on the Safe mode start window or otherwise make changes.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes