# Standard User Agent > Blend in with the most common Firefox UA Canonical page: [https://chrome-stats.com/d/standard-ua](https://chrome-stats.com/d/standard-ua) ## Overview - **ID:** `standard-ua` - **Platform:** Firefox - **Type:** Firefox add-on - **Status:** Available - **Publisher:** TN3W - **Category:** web-development,privacy-security,search-tools - **Daily users:** 1 - **Version:** 1.0.0 - **Last updated:** 2026-03-18 - **First published:** 2026-03-15 - **Size:** 36 KB - **Data as of:** 2026-09-08 - **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/standard-ua/) - **Website:** [https://github.com/tn3w/Standard-UA/issues](https://github.com/tn3w/Standard-UA/issues) ## Description Blend in flawlessly. No fingerprinting. A lightweight browser extension that standardizes your User-Agent to the most common configuration, protecting your privacy by making you look exactly like everyone else. View on GitHub Why This Extension What It Does Seamless Spoofing Sets your User-Agent to the most standard, widely used Chromium configuration. Automatically adjusts between desktop (Windows) and mobile (Android) based on your device type. Anti-Fingerprinting Updates the modern sec-ch-ua Client Hints HTTP headers dynamically on every request. Spoofs the navigator.userAgentData API accurately to ensure complex browser fingerprinting scripts see precisely the fake data instead of your real profile. Restores original navigator properties recursively like appVersion, platform, vendor, and oscpu. Zero Performance Impact Uses highly optimized declarativeNetRequest for instant network-level manipulation without holding up pageloads. Injects required overrides into the page synchronously via pure isolated-world and main-world bridge scripting. How It Works The extension operates on two levels:
  1. Network Level: The background Service Worker configures declarativeNetRequest to intercept and dynamically overwrite network headers (User-Agent, sec-ch-ua, sec-ch-ua-mobile, sec-ch-ua-platform) and sets a custom internal Server-Timing header to pass configuration instantly.
  2. Execution Environment Level: Content scripts intercept the Server-Timing headers even before the page's code runs, modifying prototype chains to override Javascript APIs (navigator.userAgentData, navigator.userAgent) within both MAIN and ISOLATED worlds natively seamlessly.
Security & Privacy Zero tracking, analytics, or telemetry. No remote APIs accessed or servers communicating. Operates entirely offline using a statically analyzed popular UA string inline. Open source and completely auditable. License Copyright 2026 TN3W Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ## Rankings - #102,812 — Overall - #71 — agenda - #185 — agent ## Permissions and access ### Permissions - `scripting` - `declarativeNetRequest` ### Host permissions - `` ### Content script matches - `*` ## Safety - **Risk impact:** Moderate risk impact - **Risk likelihood:** Moderate 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 has low user count. Unpopular extensions may not be stable or safe. > Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing). ## Similar extensions and apps - [User-Agent Changer](https://chrome-stats.com/d/user-agent-changer2901) — 45 users - [Simple UserAgent Spoofing](https://chrome-stats.com/d/simple-useragent-spoofing) — 1 users - [Chrome UA Spoofer](https://chrome-stats.com/d/chrome-ua-spoofer) — 2 users - [User-Agent Auto Spoofer](https://chrome-stats.com/d/user-agent-auto-spoofer) — 8 users - [User-Agent Switcher and Manager](https://chrome-stats.com/d/user-agent-string-switcher) — 83,517 users, 4.08 / 5 - [Ultimate Privacy Guard](https://chrome-stats.com/d/ultimate-privacy-guard) — 1 users - [Random User-Agent (Switcher)](https://chrome-stats.com/d/random_user_agent) — 3,968 users, 4.00 / 5 - [Chrome Mask](https://chrome-stats.com/d/chrome-mask) — 55,923 users, 4.47 / 5 - [Advanced User-Agent](https://chrome-stats.com/d/advanced-user-agent) — 4 users - [User Agent Modifier](https://chrome-stats.com/d/user-agents-modifier) — 3 users - [Unga Bunga User-Agent](https://chrome-stats.com/d/unga-bunga-user-agent) — 32 users, 4.50 / 5 - [Winston's User-Agent Switcher](https://chrome-stats.com/d/winston-s-user-agent-switcher) — 3 users, 5.00 / 5 --- Source: [Chrome-Stats](https://chrome-stats.com/d/standard-ua)