Merlin
JShelter

JShelter

JShelter controls the APIs provided by the browser. The goal is to improve the privacy and security of the user running the extension.

  • JShelter
  • JShelter
  • JShelter
  • JShelter
  • JShelter
  • JShelter
What is JShelter?
JShelter is a unique Firefox extension that improves the privacy and security of your web browsing. It restricts the amount of data websites can gather by controlling the APIs provided by the browser. It can allow or forbid certain actions, reduce the precision of geolocation, and act as a protective barrier against potential threats. JShelter ensures users have control over what their browsers are doing.
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Merlin
Stats
Users: 542 ▼ -14
Rating: 4.53 (38)
Version: 0.18 (Last updated: 2024-04-19)
Creation date: 2019-02-27
Weekly download count: 24
Firefox on Android: Yes
Risk impact: High risk impact
Risk likelihood: Moderate risk likelihood
Manifest version: 2
Permissions:
  • storage
  • tabs
  • webRequest
  • webRequestBlocking
  • webNavigation
  • dns
  • <all_urls>
  • notifications
Size: 447.14K
URLs: Website
Stats date:

Chrome-Stats Rank

# 4279 ▼ 23
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Other platforms

JShelter
JShelter (v0.18)
4.55 (22) 3,000
Not available on Edge
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Merlin
Summary
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What is JShelter?

JShelter is a browser extension to give back control over what your browser is doing. A JavaScript-enabled web page can access much of the browser's functionality, with little control over this process available to the user: malicious websites can uniquely identify you through fingerprinting and use other tactics for tracking your activity. JShelter aims to improve the privacy and security of your web browsing.

How does it work?

Like a firewall that controls network connections, JShelter controls the APIs provided by the browser, restricting the data that they gather and send out to websites. JShelter adds a safety layer that allows the user to choose if a certain action should be forbidden on a site, or if it should be allowed with restrictions, such as reducing the precision of geolocation to the city area. This layer can also aid as a countermeasure against attacks targeting the browser, operating system or hardware.

Please see the FAQ (https://jshelter.org/faq/) and our blog (https://jshelter.org/blog/) for more information about the extension.

What is the threat model?

See https://jshelter.org/threatmodel/

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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
  • Extra protection when JS must be enabled
  • Easy to use compared to NoScript
  • Eliminates tracking between sites
Cons
  • Breaks many websites, especially those using CAPTCHA
  • High CPU and RAM usage in some cases
  • Notifications can become noise
Most mentioned
  • Breaks too many websites
  • High CPU and RAM usage
  • Eliminates tracking between sites
Recent reviews
I had to disable this after the upgrade to Firefox 125.0.1 because it caused very high CPU (100%) and RAM (20G+) usage for multiple hours, without end. I used about:memory to discover that this was the culprit. After I disabled JShelter, the CPU usage and RAM dropped.
by Adrian F., 2024-04-22
A great tool that everyone should be using, even if it's not perfect. I recommend it to anyone that will listen. On rare occasions some sites will break because they're using a really aggressive captcha or spam detection platform. Lowering the settings on JShelter and refreshing fixes this. I also disagree that notifications should be shown by default, if at all. Every site is using fingerprinting of some sort nowadays, so you just get a notification every time you go to a site and the notifications become noise.
by ti-ap, 2024-02-19
View all user reviews
Safety
Risk impact

JShelter is risky to use as it requires a number of sensitive permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install JShelter if you trust the publisher.

Risk likelihood

JShelter is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

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