Content blocking

Revision Information
  • Revision id: 170166
  • Created:
  • Creator: AliceWyman
  • Comment: added note about "Do Not Track"
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: AliceWyman
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: No
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Revision Content
Please update your version of Firefox for the latest features and security updates.

Content blocking is a collection of Firefox settings allowing you to block content that affects privacy and browsing performance. Starting in Firefox version 63, content blocking includes blocking for third-party tracking cookies and the feature previously called Tracking Protection, which blocks all detected trackers.

When Firefox detects content that can be blocked on a website, a shield FirefoxShieldIcon icon will appear in your address bar.


Select the information Site Info button icon or the shield FirefoxShieldIcon icon to expand the Control Center for the site. This provides more information about the type of content Firefox has detected, such as detected trackers and trackers set by third-party cookies. (The Control Center is also where you manage your permission settings for this site.)


If trackers or third-party tracking cookies are not found on a site, the content blocking shield will not appear and the Control Center will display the message "No blockable content detected on this page".

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Turn Content Blocking on or off

Content blocking includes settings for trackers and tracking cookies. By default, Firefox blocks trackers only in private windows and doesn’t block third-party tracking cookies at all. You can change your optionspreferences to block trackers all the time or to not block any content at all. You can also set your optionspreferences to block just third-party tracking cookies or all third-party cookies.

To change your optionspreferences, click the Firefox menu button fx57menu and select Content Blocking. This takes you to your Content Blocking optionspreferences.


  • To block trackers for all browsing sessions, change the All Detected Trackers setting from Only in private windows to Always.
  • To turn off Content Blocking for detected trackers, deselect the checkbox for All Detected Trackers.
  • Select the Third-Party Cookies checkbox to block third-party tracking cookies. To block all third-party cookies, change the setting from Trackers (recommended) to All third-party cookies (may cause websites to break). For more information, see Third-party cookies and Firefox tracking protection.
Note: You can also set Firefox to always send websites a Do Not Track signal. See the How do I turn on the Do Not Track feature? article to learn more.

Turn Content Blocking off on individual sites

Sometimes, Content Blocking can prevent pages or parts of pages from loading. If Content Blocking interferes with your browsing, you can disable it for the site you are visiting. The shield icon appears in the address bar when Firefox is actively blocking content on a page.

  1. Select the shield FirefoxShieldIcon icon or the information Site Info button icon to expand the Control Center panel.
  2. Click the Disable Blocking for This Site button in a normal browsing window or the Disable Blocking Temporarily button in a private window (see below) to disable blocking for the website.
  3. Once Content Blocking is disabled, a shield icon with a strikethrough will appear in your address bar.
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  4. To resume content blocking, expand the Control Center panel and select Enable Blocking For This Site.

Content Blocking in Private Browsing

Since Private Browsing doesn’t save information about your browsing session, when you disable content blocking for a site, it only lasts for your current session. When you start a new private browsing session, your content blocking settings will be restored for all sites. If you’ve disabled content blocking for a site while in a normal browsing window, Firefox will continue to disable content blocking for this same site when in a private window.

Block lists in Firefox

You can change the block list used to block trackers. By default, content blocking uses the basic protection list. You can change this to use the strict protection list instead.

  • The basic protection list blocks commonly known analytics trackers, social sharing trackers, and advertising trackers. However, the basic protection list allows some known content trackers so that fewer pages break or fail to load.
  • The strict protection list blocks all known trackers, including analytics trackers, social sharing trackers and advertising trackers as well as content trackers. The strict list will break some videos, photo slideshows, and social networking features.

Change your block list

  1. Expand the main Firefox menu button fx57menu and select Content Blocking.
  2. Select the Change block list link.
  3. Choose the block list you want to use.
  4. Select Save Changes.
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