ContainSite

Name: ContainSite
Rating: 5 (1 reviews)
Author: salmutt

By: salmutt Add-on

Per-container fingerprint isolation — each container gets its own unique device identity

Overview

Firefox Add-ons Store

Daily users

Data as of 2026-08-20

Rating:

5.00

(1)

Version:

0.7.0

Last updated: 2026-04-08

Features & Capabilities

Every website you visit is automatically placed in its own isolated container with a unique, deterministic device fingerprint. Sites cannot share sessions, cookies, or correlate you through browser fingerprinting.

Features:

Automatic per-site containers — no configuration needed
20 spoofed fingerprint vectors: Canvas, WebGL, AudioContext, Navigator, Screen, Timezone, WebRTC, Fonts, Font API, ClientRects, Plugins, Battery, Connection, HTTP Headers, Speech Synthesis, matchMedia, Performance Timing, Storage Estimate, Gamepad, import/export
HTTP header spoofing — User-Agent, Accept-Language, and Client Hints per container
Cloudflare-safe mode — per-container shield toggle that disables vectors causing bot detection (UA, platform, WebGL, screen) while keeping undetectable vectors active (canvas, audio, fonts, timezone)
Auth-aware — login redirects stay in the originating container
Preserve original tab — cross-domain link clicks open a new container tab, keeping your current page open
Options page to toggle individual vectors, whitelist domains, auto-prune inactive containers, and manage containers
Per-container vector overrides — fine-tune spoofing for individual sites
Import/export all settings

Works alongside Firefox Multi-Account Containers. No external dependencies. Zero data collection.

User Growth & Download Statistics

Add-on

By:

salmutt

Daily users:

Rating:

5.00

(1)

Version:

0.7.0 Last updated: 2026-04-08

Version code:

6212252

Creation date:

2026-03-01

Risk:

Permissions:

contextualIdentities
cookies
storage
tabs
webRequest
webRequestBlocking
<all_urls>

Size:

64.48KB

Email:

co*****@salmutt.dev

URLs:

Website

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-08-20

Compare stats and ranking:

Ranking

# 75,515 ▲ 107

Other rankings

#150 in contain keyword 33 ▼ 2

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

salmutt

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/containsite/

Email:

co*****@salmutt.dev

Website:

https://github.com/SalMutt/ContainSite

User Reviews

So far the plugin seems solid and contains each site effectively through my testing. Really good idea for privacy.

by Do*****, 2026-03-04

View all user reviews ›

Is ContainSite Safe?

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

ContainSite requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details

Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
Critical ****** ****** ** *** ********* ****** * *********** ******** **** ** ** *** ******* *** ****** **** **** *** ******* *****
High ****** *** ********* ** ******* *** ******* ******* ** ****** *** *** ******** ******

Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

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

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Medium **** ********* *** ***** ** *** **** * ******* *** ********** *** *** ** ****** ** *****
Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
Good **** ********* *** **** **** *******