You can now enable First Party Dynamic Isolation in Firefox 77

Last update on April 14, 2020 In venkat

The Nightly version of Mozilla Firefox 77 has Received a new custom mode option for enhanced tracking protection in privacy and security settings to allow users to enable the “dynamic first party isolation” feature in the Firefox browser, the feature can also be enabled by changing a preference value in about: config.

As of Firefox 53, Mozilla has hidden the first-party isolation feature behind a preference called privacy.first party.isolate, enabling it may cause certain sites to break. Over the years, Mozilla has built stronger privacy protections into Firefox in the form of improved tracking protection or content blocking modes. As of now, Firefox browser with standard ETP blocks tracking cookies, social media trackers, tracking content in private windows, fingerprints and crypto miners by default. Users who choose custom mode have the luxury of choosing which trackers and scripts to block.

So far, custom setting allows blocking these types of cookies in Firefox browser

• Cross-site and social media trackers
• Cookies from unvisited websites
• All third-party cookies
• All the cookies.

In addition to the above, the custom setting for Advanced Tracking Protection in Firefox Nightly provides another new option for cookies in the drop-down menu:

cross-site and social media trackers and isolate remaining cookies

Choosing this option may cause some websites to hang where you are unable to enter them. Dynamic FPI can also be enabled by changing the following preference in about:config to 5.

network.cookie.cookieBehavior

To test the feature, launch Firefox Nightly

1. Click on the menu, select Options

2. Privacy & Security > Custom,

3. Select “Cross-site and social media trackers and isolate remaining cookies”

You need to reload all tabs or you can restart your browser for the same.

When selecting the option, Firefox Nightly displays a warning at the bottom warning that “Blocking trackers and isolating cookies may affect the functionality of some websites”.

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