Merlin
Javascript Firewall

Javascript Firewall

Block JavaScript of unwanted origin.

What is Javascript Firewall?
JavaScript Firewall is a Firefox add-on that enables advanced users to block JavaScript from unwanted origins. It provides a user-friendly interface to configure rules for allowing or blocking JavaScript code, data requests, and external content on specific websites. The add-on allows users to create domain-specific rules and provides options for managing settings and rules. With JavaScript Firewall, users can enhance their web browsing security and control the execution of JavaScript on different websites.
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Merlin
Stats
By: Bill
Users: 13 ▼ -1
Rating: 4.53 (15)
Version: 1.4 (Last updated: 2022-05-10)
Creation date: 2019-09-30
Weekly download count: 1
Firefox on Android: No
Risk impact: High risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
Permissions:
  • storage
  • webRequest
  • webRequestBlocking
  • webNavigation
  • *://*/*
Size: 17.56K
URLs: Website
Stats date:

Chrome-Stats Rank

# 23066 ▼ 848
Other rankings
#18 in javascript keyword 23 #84 in script keyword 29

Other platforms

Not available on Chrome
Not available on Edge
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Merlin
Summary
Analyze keywords

This extension is intended for advanced users. Some websites will require configuration to work properly.

For each website, you can decide from which domains JavaScript is allowed. By default, only scripts from the same domain than the website are allowed.

Interface

  • The table shows how many requests have been blocked or allowed on the web page for each domain. Each column of the table represents a type of request:
    • JS: javascript code: <script> and Workers
    • XHR: data request: XMLHttpRequest, Fetch, WebSocket, Beacon, ping, and Content-Security-Policy-report
    • FRAME: external content: <iframe>, <frame>, <object> and <embed>
    The color of a cell indicates whether it has been blocked or allowed :
    • dark red: blocked explicitly
    • light red: blocked by a more general rule
    • light green: allowed by a more general rule
    • dark green: allowed explicitly
    To create a rule, click on a cell until you get the desired color.
  • The drop-down list at the top left indicates on which websites the rules apply. By default, a rule only applies to the website's domain and it's subdomains. If you want to create a rule that applies to all websites, select "all websites".
  • The 5 buttons:
    • Reload: For the new rules to take effect, the page must be reloaded.
    • List: Manage the settings and the rules you have created. You can use the text mode to manually edit your rules (4th screenshot)
    • Disable/Enable: When disabled, the addon will not block anything for the current tab but will still count requests.
    • Delete: Delete the rules you have created for the current website.
    • Arrow: Display all the parent domains. It makes it possible to create a rule which will apply to all its subdomains.
  • The badge on the icon shows the number of blocked requests.
Examples
  • Make Youtube works (1st screenshot)
    1. Go to a Youtube video and click on the addon icon
    2. Click on the arrow button to display the parent domains
    3. Allow XMLHttpRequest (XHR) for googlevideo.com
    4. Reload the page
  • Allow embedded YouTube videos on all websites (2nd screnshot)
    1. Go to a Youtube video
    2. Click on the arrow button to display the parent domains
    3. Select "all websites" in the drop-down list
    4. Allow JS, XHR and FRAME for www.youtube.com and XHR for googlevideo.com
  • Allow everything for a website (3rd screenshot)
    1. Make the "JS", "XHR" and "FRAME" cells dark green
Other examples can be found on the wiki.
See more
User reviews
Mann kann die Scripte auf jeder Seite separat anpassen. Besser wie viele andere Scriptblocker, wo man gar nichts einstellen kann. Ich kann diesen empfehlen nach meinen Erfahrungen. Wichtig ist nicht die Cache im Browser Löschen dort werden die Einstellungen gespeichert!
by Killer2005de, 2023-04-18
View all user reviews
Safety
Risk impact

Javascript Firewall 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 Javascript Firewall if you trust the publisher.

Risk likelihood

Javascript Firewall has earned a fairly good reputation and likely can be trusted.

Upgrade to see risk analysis details
Screenshots
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