That's kind of crazy... but there are some add-ons and settings which can misidentify your browser.

For settings, could you take a look at this article: How to reset the default user agent on Firefox.

For add-ons, it's hard to guess what you might have, but you could test in Firefox's Safe Mode to deactivate ALL extensions to see whether that makes a difference. (More info: Diagnose Firefox issues using Troubleshoot Mode)

You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

Not all add-ons are disabled: Flash and other plugins still run

After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any difference?

I tried it in safe mode and it looked the same.

I guess I didn't make myself clear. When using Firefox the only website that doesn't open correctly is Mozilla's website. When I use Internet Explorer, or Maxthon browsers and go to Mozilla's website it open the way it should. Here is a screen shot of Mozilla"s website when I use Firefox.

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It's hard to understand that pile of text because it seems to be a lot of contradictory information. All of that is visible?

It sounds as though some content normally used by the site to manage the page layout is not loading. I have attached a screen shot of what the site normally looks like, where the inapplicable messages are hidden. Are you able to capture a screen shot image and attach it to a reply? This article has tips on that: How do I create a screenshot of my problem?

Also, can you visit my browser test page and copy the user agent string (first one in red) detected by the server? https://jeffersonscher.com/res/jstest.php

What is the useragent that your Firefox browser is displaying to websites?

It was likely modified by you either by a useragent related extension or manually in about:config or preference. Or it could be due to a proxy or even a external software that changes what the browser identifies itself as online.

Here is the useragent from the test page using Internet Explorer:

Browser "User Agent" string: Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko

Here is the useragent from the test page using Firefox:

Browser "User Agent" string: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:33.0) Gecko/20100101 Firefox/33.0

Yes I see everything that I sent you. I tried getting a screenshot from Firefox and I couldn't paste here (I am using IE to answer this)

PROBLEM SOLVED

Ok James, I was able to figure out the problem. I use the Avast Anti-Virus program. It offers a feature called "Home Network Security" When I updated to the latest version I thought I would give that feature a try. I went and turned that feature off and was able to get Mozilla's website to load like it should. What I don't understand is why it only did that with Mozilla's website and only when using Firefox. It didn't do that using IE or Maxthon browsers.

Anyways thank you so much for replying to my problem and trying to solve it. When you said "Or it could be due to a proxy or even a external software that changes what the browser identifies itself as online. It made me remember the change I made with the Avast Anti-Virus program.