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Preview of Visilant

Visilant by Xcoder

Protection against phishing sites based on your personal site visiting statistics.

Available on Firefox for Android™Available on Firefox for Android™
5 (1 review)5 (1 review)
4 Users4 Users
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Screenshots
Instantly check visit history for the current site and its sibling domains using popup. In this example, notice how Visilant exposes the fake rnicrosoft[.]com (mimicking Microsoft) — the uppercase display setting clearly reveals the 'RN' vs 'M' deception.Spot the real domain instantly. In this example, the attacker tries to hide behind google.com, but Visilant highlights the true destination (totaly-legit.com) so you don't fall for the trick.Example of the in-page warning when trying to type text on a site with a number of visits that is lower than threshold to be considered safe. It is the most useful in dealing with phishing cloned site when you now you visited original site a lot.Example of the in-page warning when site is trying to trick you into pasting commands into terminal (that were copied into buffer by the malicious site). If you sure you didn't copied anything and see this warning, chances are that this site is malicious.Settings pageSettings page (continued)
About this extension
Visilant is a lightweight, open-source extension designed to protect you from phishing sites, clone phishing, and homograph attacks. It helps you spot fake websites that try to steal your credentials by visually mimicking legitimate services.

How it works:
Most phishing websites are those you have never visited or visit very rarely. Visilant tracks your visit history locally and provides two layers of protection:
* Proactive — analyzes links on the page before you click them, revealing the destination domain, your familiarity with it, and flagging URL mismatches and suspicious domains.
* Reactive — alerts you when you interact with an "unfamiliar" site (typing, pasting, copying).

Unlike traditional antivirus solutions, Visilant can alert you about phishing sites the moment they are created — without waiting for blacklist updates.

Key Features:
* Link Safety (Proactive): A tooltip on hover (or click) shows each link's destination domain, your visit count, and familiarity status. Detects URL mismatches where visible link text differs from the real destination, flags homograph-attack domains, and can intercept navigation to unfamiliar sites with a full-screen confirmation dialog.
* Shortened URL Detection: Resolves short links (bit.ly, t.co, and others) to reveal the real destination — a classic trick in clone phishing. Works on-demand or automatically, supports custom shortener lists and remote-updated lists.
* Homograph Protection: Visilant highlights the actual domain name and supports Punycode display to prevent attacks where special characters look like Latin letters (e.g., a fake amazon.com).
* Interactive Dashboard: Click the icon to view detailed visit statistics, sort your site history, toggle per-site anti-tampering, and adjust display settings on the fly.
* Hardened Security: Includes anti-tampering protection that detects and alerts you if a malicious website attempts to disable or hide the extension. Can be disabled per-site for trusted sites that trigger false alarms.
* Theming & Responsive UI: Light, dark, or system-matching theme. Works in popup, in a tab, and on mobile-form-factor windows.

GETTING STARTED
1. Install the extension.
2. (Highly Recommended) Pin the Visilant icon to your browser toolbar for constant visibility.
3. Click the Visilant icon to open the Dashboard (Popup).
4. Click the Settings (gear) icon to configure preferences.
5. Import your browser history to populate the visit counter. This drastically reduces false positives for sites you already use.

CONFIGURATION INCLUDES:
1. Familiarity Threshold: How many visits make a site "familiar" (default is 10).
2. Link Safety:
* Tooltip trigger: hover, left-click (safest — prevents navigation until review), or right-click (context-menu item).
* Visit count visibility in tooltips: always, never, only for unfamiliar, or only for familiar.
* Optional navigation intercept before visiting unfamiliar sites.
* Shortened URL detection: off, on-demand button, or automatic; full URL or domain only; redirect chain trace; arbitrary URL resolution; custom shortener domains; remote lists.
* Scope: all websites, whitelist, or blacklist.
3. Display & Sorting:
* Toggle Domain Highlighting to easily spot the real domain extension.
* Switch between Unicode and Punycode for international domains.
* Sort site history by name or visit count.
4. Notifications:
* When to show: typing, copying, or both.
* Style: browser notifications, in-page warnings, or both.
5. Anti-Tampering: Exclude specific domains from tamper detection.
6. Appearance: Light, dark, or system theme.

PRIVACY & PERMISSIONS
Visilant is open-source and operates locally:
1. All data remains on your computer. Nothing is sent to external servers.
2. Permissions:
* Tabs, Storage, Host Permissions: Required for core functionality (tracking visits, analyzing links, detecting inputs).
* Notifications: Required to alert you if a malicious site attempts to tamper with the extension.
* Context Menus: Required to provide the "Check link safety" right-click option.
* Browser History: Optional. Required only if you choose to import history (recommended).

LIMITATIONS
1. Not a Malware Blocker: Visilant focuses on social engineering and spoofing. It does not block malware downloads or trackers.
2. Relies on Awareness: The extension warns you, but you must decide to act on that warning.
3. False Positives and Negatives: Legitimate sites with low visit counts may trigger warnings (false positives), while phishing sites visited repeatedly (or hijacked sites) may go unflagged (false negatives).
4. Script Injection: Visilant injects a script to detect inputs and analyze links. While the extension includes Anti-Tampering Protection to detect if a site tries to remove this script, pinning the extension icon remains the most reliable visual indicator.
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Permissions and data

Required permissions:

  • Display notifications to you
  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access browsing history
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
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Version
1.9.1
Size
286.37 KB
Last updated
2 days ago (Apr 19, 2026)
Related Categories
  • Privacy & Security
License
MIT License
Privacy Policy
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Version History
  • See all versions
Tags
  • anti malware
  • security
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