# JavaScript-Java Bridge

> A replacement for the Java Plugin so Java Applets without graphics continue to work on browsers that no longer support NPAPI plugins. Java's LiveConnect API is emulated — data & method calls can be exchanged, and Java can manipulate the webpage DOM.

Canonical page: [https://chrome-stats.com/d/javascript-java-bridge](https://chrome-stats.com/d/javascript-java-bridge)

## Overview

- **ID:** `javascript-java-bridge`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Removed
- **Publisher:** Advanced Machine Controls
- **Daily users:** 27,823
- **Weekly downloads:** 343
- **Rating:** 4.29 / 5 (21 ratings)
- **Version:** 1.82
- **Last updated:** 2026-04-08
- **First published:** 2019-03-01
- **Size:** 22 KB
- **Data as of:** 2026-06-22
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/javascript-java-bridge/)
- **Website:** [https://github.com/mrj/jsjbridge](https://github.com/mrj/jsjbridge)

## Description

JavaScript-Java Bridge is a Firefox extension and Java library designed to replace the deprecated Java Plugin, enabling Java Applets without graphics to work in browsers that no longer support NPAPI plugins. It emulates Java's LiveConnect API, allowing bidirectional data and method exchange between Java and JavaScript, including DOM manipulation from Java code.

This extension offers an efficient alternative to rewriting Java Applets as backend APIs communicating via AJAX or modern frameworks. It maintains the remote procedure call and remote DOM manipulation paradigm, simplifying synchronization between frontend and backend. Licensed under the DevWheels Licence, it supports free use for testing and development, with a licensing fee for production installations. Developers are encouraged to contribute enhancements to the main project for collaborative improvement.

## Permissions and access

### Permissions

- `nativeMessaging`
- `storage`

### Content script matches

- `<all_urls>`

## Safety

- **Risk impact:** Moderate risk impact
- **Risk likelihood:** High risk likelihood

### Analysis details

- Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
- This extension is not longer available in the store

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

## Review summary

Several reviews indicate that the JavaScript-Java Bridge add-on does not function properly, with users reporting that it 'DOES NOT WORK.' Additionally, there are repeated posts containing promotional content and links not directly relevant to the add-on's functionality, suggesting possible spamming or irrelevant comments rather than substantive feedback.

### Cons

- Does not work as expected or is non-functional

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Source: [Chrome-Stats](https://chrome-stats.com/d/javascript-java-bridge)