How to stop Firefox from automatically making connections without my permission

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  • Revision id: 24114
  • Created:
  • Creator: michro
  • Comment: Reset All Add-ons to Update Automatically (it's "Automatically", not "Manually")
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: Ibai
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: Yes
  • Readied for localization:
  • Readied for localization by: Ibai
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Some people are particularly concerned about the connections Firefox makes to the Internet, especially when such connections are made with no apparent cause. This article will explain the various reasons why Firefox may make a connection to the Internet, and how you can stop it from doing so if you so desire.

Loopback connection

A loopback connection (to IP address 127.0.0.1) can be made by Firefox on non-Unix machines. In this case the browser is communicating with itself as expected, and it is not recommended that this communication be blocked. See bug 100154 for more information.

Live Bookmarks updating

Live Bookmarks automatically reload themselves on a regular basis, and in doing so will make a connection to the Internet. Deleting all your Live Bookmarks will stop these connections from being made.

Auto-update checking

Warning: Disabling update checking is not recommended and will leave you open to security vulnerabilities that get fixed in newer versions.

Firefox occasionally checks to see if any updates are available for itself, for your add-ons (extensions, themes), and for your search engines. To disable these checks:

  1. At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

    Click the menu button New Fx Menu and choose Options.Preferences.

  2. Select the Advanced icon.
  3. Select the Update tab.
  4. Uncheck Firefox, Add-ons, and Search Engines.Uncheck Automatically check for updates to: and Search Engines.Check Never check for updates (not recommended: security risk) and uncheck Search Engines.

Firefox also checks to see if any updates are available for your add-ons (extensions, themes). To disable this check:

  1. At the top of the Firefox window, click on the Firefox buttonOn the menu bar, click on the Tools menuAt the top of the Firefox window, click on the Tools menu, and then click Add-ons. The Add-ons Manager tab will open. Click the menu button New Fx Menu and choose Add-ons. The Add-ons Manager tab will open.

  2. In the Add-ons Manager tab, select the Extensions panel.
  3. At the top of the tab, click the Tools for All Add-ons menu and uncheck Update Add-ons Automatically, then select Reset All Add-ons to Update Automatically.

Home page loading

Your home page may be loading. To change your home page to something that doesn't generate connections to the Internet:

  1. At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

    Click the menu button New Fx Menu and choose Options.Preferences.

  2. Select the General panel.
  3. Either set When Firefox starts to Show a blank page or set it to Show my home page and click Restore to Default.

Anti-phishing list updating

Warning: Disabling the anti-phishing protection is not recommended, as it will leave you vulnerable to untrustworthy web-sites that might try to steal your financial information and/or your identity.

The phishing protection list may be updating itself. To turn this off:

  1. At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

    Click the menu button New Fx Menu and choose Options.Preferences.

  2. Select the Security panel.
  3. Uncheck Block reported web forgeries.

Anti-malware list updating

Warning: Disabling the anti-malware protection is not recommended, as it will leave you vulnerable to untrustworthy web-sites that might try to infect you with a virus, trojan or spyware.

The malware protection list may be updating itself. To turn this off:

  1. At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

    Click the menu button New Fx Menu and choose Options.Preferences.

  2. Select the Security panel.
  3. Uncheck Block reported attack sites.

Add-on list prefetching

Each time the Add-ons manager is opened, Firefox prefetches a list of add-ons to improve responsiveness of the Get Add-ons pane. This connection is not made if the add-ons manager is not opened.

Link prefetching

Firefox will prefetch certain links if any of the websites you are viewing uses the special prefetch-link tag. For more information, please see the Link Prefetching FAQ. To disable prefetching:

  1. In the Location bar, type about:config and press EnterReturn.

    • The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.
  2. In the about:config page, search for the preference network.prefetch-next.
  3. Observe the Value column of the network.prefetch-next row.
    • If it is set to false then do nothing.
    • If it is set to true, double-click on it to set it to false.

Extension blocklist updating

Warning: Disabling blocklist updating is not recommended and may result in you using extensions known to be untrustworthy.

Firefox may be updating its extension blocklist. For more information, see Add-ons that cause stability or security issues are put on a blocklist. To disable this:

  1. In the Location bar, type about:config and press EnterReturn.

    • The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.
  2. In the about:config page, search for the preference extensions.blocklist.enabled.
  3. Observe the Value column of the extensions.blocklist.enabled row.
    • If it is set to false then do nothing.
    • If it is set to true, double-click on it to set it to false.

Live Title updating

If you have any Live Title bookmarks, they may be updating themselves. To disable Live Title bookmarks:

  1. In the Location bar, type about:config and press EnterReturn.

    • The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.
  2. In the about:config page, search for the preference browser.microsummary.enabled.
  3. Observe the Value column of the browser.microsummary.enabled row.
    • If it is set to false then do nothing.
    • If it is set to true, double-click on it to set it to false.

Extensions

An extension you have installed may be making a connection to a website that it relies on. For example, a connection to a website to synchronize your bookmarks, a connection to a website to update a list of sites to block, etc. Or it is possible an extension could be changing the expected behavior of Firefox in other ways. For example, FasterFox extension has an option to prefetch all links.

To easily disable all of your extensions please read the Troubleshoot Firefox issues using Safe Mode article, paying particular attention to the Disable all add-ons option under the Make Changes and Restart section.

Downloads restarted

When you start Firefox, any interrupted downloads from your previous browsing session may be automatically resumed.

  1. Press Ctrl + JCtrl + Shift + Ycommand + J to open the Where to find and manage downloaded files in Firefox.
  2. Ensure nothing is currently being downloaded

Infected with malware

If your machine is infected with a virus, trojan, or spyware, then Firefox's Internet connection may be being piggybacked in order for the malware to communicate with its author or to deliver adverts onto your machine, etc. If you suspect this is the case, consider seeking specialized advice from one of these malware support sites:

Please be aware that Mozilla is not responsible for the content of third-party websites.




Based on information from Connections established on startup - Firefox (mozillaZine KB)