Firefox Defender Addon Removal Guide

Do you know what Firefox Defender Addon is?

Firefox Defender Addon is a browser extension that can be considered a potentially unwanted program and a fake alert, too. This add-on often displays a fake message that says you need to manually update your browser. It is very likely that the add-on you install on your browser will continue to spy on you. At the same time, it would not be surprising if you have more potential threats on your system. So when you remove Firefox Defender Addon, please make sure that you scan your computer with a licensed security tool.

The original website that used to distribute the annoying fake alert was When we first covered this intruder, the site was already reported but still operating. It used to be rather easy to trick users into downloading Firefox Defender Addon because the entire screen was taken over by the fake alert. This fake alert looked rather imposing and reliable. What’s more, the design and the wording of the message on the page made it look like an integral part of the Firefox setup, so it could trick quite a few users without even trying. Here is what the fake alert message looked like when users opened the website:

Firefox requires a manual update

This update is required to ensure that you are protected on the Internet.

Install Now

* This update is required

  • Protect yourself immediately on the Internet

  • Internet pages are automatically examined and possibly blocked

  • Increased protection against malware and viruses

When you have such a message on your screen, it surely looks like you should click that Install now button. However, it is important to note that all of your updates should come from your browser itself. That is to say; you would not see a third-party notification that urges you to install an update on your computer unless it is solicited by your application. This fake alert is obviously not approved by Firefox, so there is no need to pay heed to it. If it does not allow you to close the window, please remember that you can close your browser via Task Manager or simply by press Alt+F4.

What happens if you click the button though? Well, if you do “install” the update, the thing you install is Firefox Defender Addon. According to our research team, this add-on is absolutely useless. It does not defend you from cyber threats. If anything, it could be considered a threat itself. Like most of the third-party freeware applications, Firefox Defender Addon is very likely to engage in online monitoring.

We believe that it will use tracking cookies to collect information on your web browsing habits. Although it cannot collect your personal information (the program is too basic for that), it can still be quite intrusive. Also, the information it collects could be used later on for online marketing purposes. What do we mean by that? What we mean is that you could be bombarded by commercial advertisements later on.

For the most part, such behavior is more annoying than dangerous, but there are certain security risks that you should consider. That is to say, even if a certain program or application is not particularly harmful, it could still be associated with a number of security threats, so you need to avoid them.

What’s more, it would not be surprising if Firefox Defender Addon got exploited by cyber criminals to promote corrupted third-party content. Usually, that content will be associated with various marketing schemes, but there are also cases when such annoying extensions help malware reach their targets. Hence, you need to do everything to remove Firefox Defender Addon right now.

Deleting this plug-in is not complicated. You just need to remove the extension via Firefox settings. You can find the guidelines for that below this description. Nevertheless, you should also consider running a full system scan with a security tool because you might have many more unwanted or potentially harmful programs installed.

Relying on a legitimate antispyware application would help you determine just how many programs you need to remove at once. Also, security application of your choice would get rid of the threats automatically.

How to Remove Firefox Defender Addon

  1. Open the Firefox browser.
  2. Press Alt+T and click Add-ons.
  3. Open the Extensions tab.
  4. Delete Firefox Defender from the list.
  5. Restart your browser.
  6. Scan your PC with SpyHunter.

In non-techie terms:

Firefox Defender Addon may not be a genuine computer security threat, but it is still a nuisance that should not be overlooked. If you care about your system’s security (and you most certainly do), you will see to it that Firefox Defender Addon gets removed immediately. While you are at it, make sure you terminate all the other unwanted applications as well (if any).