Sieve - Site & Content Blocker Firefox

Sieve - Site & Content Blocker

Sieve has one purpose: to filter out harmful and distracting content from the web pages you visit, keeping your browsing clean, safe, and focused.

Features & Capabilities

🛡 Sieve – Content Filter & Site Blocker

The modern web is full of scams, manipulative design, toxic comments, and bottomless feeds. Sieve quietly cleans all of that up and hands control back to you — and it runs entirely on your device. No account, no sign-up, no analytics. Nothing you browse ever leaves your browser.

Everything is modular. Switch on exactly the protections you want.

🧹 ON-PAGE CLEANUP 🤬 Bad Language Filter – Masks profanity as you browse. Choose blanks (████), asterisks (f***), or lighthearted word swaps, add your own words, or enable a stricter family-safe mode. 🙊 Toxic Comment Hider – Automatically collapses hostile, hateful, and abusive comments on YouTube, Reddit, X (Twitter), and Disqus. Includes an optional AI toxicity model that runs fully on your device, plus adjustable sensitivity and per-site control. 🎭 Dark Pattern Blocker – Neutralizes manipulative design: fake countdown timers, guilt-trip "no thanks" buttons, pre-checked boxes, and manufactured scarcity ("Only 2 left!"). 🍪 Cookie Auto-Reject – Automatically rejects non-essential cookie-consent banners so you stop clicking through them. 🚫 Popup & Click Hijack Blocker – Stops popups and pages that hijack your clicks, with a one-click "allow" for sites you trust.

🚧 BLOCK HARMFUL & DISTRACTING SITES Most are off by default — switch on what fits you. The blocklists update automatically.

🎰 Gambling & Betting – Blocks online casinos, sportsbooks, and betting sites. 🔮 Prediction Markets – Blocks Polymarket, Kalshi, and similar platforms that rebrand betting as "forecasting markets." 🪙 Crypto & Investment Scams – Blocks known crypto scams, phishing, and fraud sites. 📈 Trading & Exchange Sites – Blocks exchanges and trading platforms (Coinbase, Robinhood, forex, and more) to help you stay away from speculative trading. 🔺 MLM Schemes – Blocks known multi-level-marketing sites — recruitment schemes where most participants lose money. 🦠 Malware & Phishing – Blocks known phishing, fake-login, and malware sites. ⛏ Cryptojacking – Blocks sites that secretly use your device to mine crypto, draining your battery and slowing your computer. 🏴☠ Piracy & Illegal Streaming – Blocks torrent, warez, and illegal-streaming sites (which are often malware-ridden). 🤖 AI Content Farms & Spam – Blocks mass-produced AI-generated spam articles, fake reviews, and content-farm sites that clutter search results. 🛒 Fraud & Fake Shops – Blocks known fraud, scam, and fake-shop sites (fake stores, refund scams, impersonation). ⚠ Gore & Shock Sites – Blocks a curated list of known gore and shock-content sites. 💔 Dating Sites – Blocks mainstream and hookup dating sites (Tinder, Bumble, Match, Grindr, and similar) — for shared or younger-user browsers, or your own focus. 📝 Custom Block List & Allowlist – Block any site you choose, or allow ones you trust — applied across every blocker. 🔗 URL Shortener Resolver – Reveals what's really behind shortened links (bit.ly, tinyurl, etc.) and checks them against your protections before you click.

🧘 DIGITAL WELLBEING ⏳ Doomscroll Stopper – Set a daily time limit for endless feeds (YouTube, Reddit, X, Instagram, TikTok, Facebook). When you reach it, a gentle pause screen helps you step away.

🎛 STAY IN CONTROL 🔒 Guardian Lock – Optionally set a PIN. Weakening your protection (turning a module off, or allowing a blocked site) asks for the PIN, while strengthening it is always free — a simple way to lock in your good intentions, for yourself or your household. 📊 Protection Dashboard – See exactly what Sieve blocked for you, today and this week.

🔐 PRIVACY FIRST Sieve has no account, no analytics, and no servers collecting your data. All filtering and blocking happens locally in your browser — even the optional toxicity model runs on your own device.

✨ Free and open source.

User Growth & Download Statistics

Manifest V3 Add-on
By:
Monolab Co.
Daily users:
11 5
Version:
1.0.0 Last updated: 2026-07-07
Version code:
6338144
Creation date:
2026-07-04
Risk:
Very high risk impact High risk likelihood
Permissions:
Host permissions:
  • <all_urls>
Content scripts matches:
  • <all_urls>
  • *.twitter.com
  • *.x.com
  • *.instagram.com
  • *.tiktok.com
  • *.reddit.com
  • *.facebook.com
  • *.youtube.com
  • *.disqus.com
Size:
409.53KB
Email:
su*****@monolab.dev
URLs:
Privacy policy
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-07-30
Compare stats and ranking:

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:
Monolab Co.
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/sieve-site-content-blocker/
Email:
su*****@monolab.dev

Is Sieve - Site & Content Blocker 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.

Sieve - Site & Content Blocker requires a lot of sensitive permissions. 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.
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  • Critical ******* ****** ** *** ********* ******** ************ ****** ************** *********** *********** ************* ************ **********
  • High ****** ********* ** * ****** ******** ******** ********** * ******* ******* *****
  • 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.

Sieve - Site & Content Blocker is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • High **** ********* *** ******** ****** *** ********** *** *** ** ****** ** *****
  • High **** ********* *** *** **** ****** ********* ********** *** *** ** ****** ** *****
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