First Party Isolation

First Party Isolation

This add-on enables the First Party isolation pref. Clicking the Fishbowl icon temporarily disables it.

What is First Party Isolation?
A concept from the Tor Browser, 'First Party Isolation' is a significant privacy measure. This Firefox add-on enables users to enhance their online privacy by keying every source of browser identification with the originating domain (first party), making all access to identifiers distinct between usage on the website itself and via third-party sources. In essence, it is a powerful alternative to blocking third-party cookies that works more comprehensively.
Merlin
Stats
By: freddyb
Rating: 4.12 (42)
Version: 1.4.0 (Last updated: 2021-01-14)
Creation date: 2017-10-20
Weekly download count: 39
Firefox on Android: Yes
Risk impact: Low risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
Permissions:
  • privacy
Size: 112.09K
URLs: Website
Stats date:

Other platforms

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Not available on Edge
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Merlin
Summary

This add-on enables First Party isolation. Clicking the Fishbowl icon or removing the add-on disables it again.

First Party Isolation, also known as Cross-Origin Identifier Unlinkability is a concept from the Tor Browser. The idea is to key every source of browser identification with the domain in the URL bar (the first party). This makes all access to identifiers distinct between usage in the website itself and through third-party. Think of it as blocking Third-party cookies, but more exhaustively. Here are Firefox's implementation details about First Party Isolation.

User reviews
User reviews summary
These summaries are automatically generated weekly using AI based on recent user reviews. Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate, spammy, or outdated.
Pros
  • Easy to disable FPI with a click
  • Simple and clean add-on
  • Does what it needs to do with just a click
  • Complete privacy add-ons with no conflicts
Cons
  • Does not work properly on Ubuntu Linux
  • FPI cannot be enabled without restarting the extension
  • Apple iCloud in the browser doesn't load
Most mentioned
  • Easy to disable FPI with a click
  • Simple and clean add-on
  • Complete privacy add-ons with no conflicts
Recent reviews
View all user reviews
Safety
Risk impact

First Party Isolation is relatively safe to use as it requires very minimum permissions.

Risk likelihood

First Party Isolation has earned a fairly good reputation and likely can be trusted.

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