Content blocking

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  • Revision id: 175190
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  • Creator: AliceWyman
  • Comment: rearranged and reworded some content, added back Private Browsing section for fx65
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  • Reviewed by: AliceWyman
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Please update your version of Firefox for the latest features and security updates.

Some websites use trackers that can monitor your activity across the Internet. Content blocking is collection of Firefox settings that block many of these third-party trackers. It keeps your browsing more private so information about you won’t be invisibly tracked, stored, and shared between websites.

In some cases, blocking trackers keeps parts of pages or entire pages from loading. It’s easy to disable blocking on sites you trust. You can also customize your content blocking preferences to block more or fewer trackers.

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.

How to block more or fewer trackers

By default, Firefox protects you from being tracked in Private Windows using a basic list of known trackers provided by Disconnect. Firefox allows some trackers so websites function properly. You can change your settings to block trackers all the time, to block trackers from Disconnect’s strict list, or to not block any trackers at all.

To adjust your settings:

  1. Click the menu button fx57menu .
  2. Click Content Blocking. This takes you to the Content Blocking section in your Firefox OptionsPreferences Privacy & Security panel.
    Fx65ContentBlocking
  3. Choose your content blocking settings:
  • Standard Only blocks known trackers in Private Windows. This is the default setting. To restore to defaults at anytime, select Standard.
  • Strict Blocks trackers in all windows and third-party tracking cookies.
  • Custom Lets you choose what to block. You can also turn off all content blocking in Custom.

You can also set Firefox to always send websites a Do Not Track signal. See How do I turn on the Do Not Track feature? to learn more.

Custom settings:

Aggressive Tracking Protection

  1. Select Custom.
  2. From the dropdown, change Only in Private Windows to In all windows.
    content block custom all windows
  3. Click the Change block list link.
  4. Select the Disconnect.me strict protection check box.
  5. Click Save Changes.
  6. Select Cookies. Third-Party Trackers is the default setting. Select more aggressive cookie protections from the dropdown.
    • For more information about blocking cookies, see this article.

Remove all protections

You can also remove all the protections offered by Content Blocking, which effectively disables the feature.

  1. Select Custom.
  2. Clear (deselect) the Trackers check box.
  3. Clear (deselect) the Cookies check box.

How to detect when content blocking is on

When Firefox is blocking content on a website, a shield icon Address bar shield will appear in your address bar.

url shield 65

Select the shield icon Address bar shield or the information icon site info icon to expand the Control Center panel. This provides more information about the content Firefox is blocking, such as trackers or third-party tracking cookies.

content blocking panel 65

The content that is blocked will depend on the website and your settings. Click on the arrows > to the right of Trackers and Cookies, to see what content has been blocked or permitted on a specific site.

blocked cookies 65

Blocked content will be labeled as Blocked and greyed out.

Turn content blocking off on individual sites

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

  1. Select the shield icon Address bar shield or the information icon site info icon to expand the Control Center panel.
    content blocking panel 65
  2. Click on Turn off Blocking for This Site to disable blocking for the website in a normal browsing window. If you're in a Private Window, click on Turn off Blocking Temporarily (see below).
    • Once Content Blocking is disabled, a shield icon with a strikethrough shield icon strikethrough will appear in your address bar.
  3. To turn content blocking back on, expand Control Center panel by clicking the shield or the site information button site info icon and click on Turn on 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 Disconnect.me basic protection list. You can change this to use the Disconnect.me 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. Click the menu button fx57menu .
  2. Select Content Blocking.
  3. Select Custom.
  4. Click the Change block list link.
  5. Choose the block list you want to use.
    Fx63BlockLists
  6. Click Save Changes.

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.

Fx63menuContentBlocking

  • 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 Disable third-party cookies in Firefox to stop some types of tracking by advertisers.

Note: You can also set Firefox to always send websites a Do Not Track signal. See How do I turn on the Do Not Track feature? to learn more.

How to detect when Content Blocking is on

When Firefox is blocking content on a website, a shield FirefoxShieldIcon icon will appear in your address bar.

Fx63ContentBlockingURL

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 blocked, 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.)

Fx63ContentBlocking-details

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

no blockable content 63

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.

Fx63ContentBlockingURL
  1. Select the shield FirefoxShieldIcon icon or the information Site Info button icon to expand the Control Center panel.
    Fx63ContentBlocking-DisableBlocking
  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.
    blocking disabled 63
  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.

Turn Content Blocking on or off in private windows

Content blocking is turned on by default in Private Browsing windows.

Fx63PrivateBrowsingHomePage-ContentBlockingON

Click the switch next to Content Blocking on the Private Browsing home page to turn it off or back on. If you don't see a Content Blocking switch, it means that you've set Firefox to always block all detected trackers for all browsing sessions (see above).

Block lists in Firefox

You can change the block list used to block trackers. By default, content blocking uses the Disconnect.me basic protection list. You can change this to use the Disconnect.me 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. Click the Change block list link.
  3. Choose the block list you want to use.
  4. Click Save Changes.
Fx63BlockLists