LLCAI Labs
User-Agent Switcher · Support

Support & FAQ

How to install and use the User-Agent Switcher extension, plus answers to common questions.

1. How to install

User-Agent Switcher is a Manifest V3 Chrome extension. If you received a packaged .zip or the source folder, you can load it locally:

  1. Open Chrome and go to chrome://extensions.
  2. Turn on Developer mode (top-right corner).
  3. Click Load unpacked and select the folder that contains the manifest.json file.
  4. The User-Agent Switcher icon appears in your toolbar — click it and choose Pin so it stays visible.

Once the extension is published to the Chrome Web Store, installation will also be available from the store listing.

2. Choose a preset User-Agent

Presets let you switch between common browsers and devices in one click:

  1. Click the toolbar icon to open the popup.
  2. In the Quick switch area, tap a device button — Android, iPhone, iPad, Windows, Mac, Edge or Firefox.
  3. The active identity is highlighted. The current identity is shown at the top of the popup (for example, “Current: iPhone”).

3. Set a custom User-Agent

  1. Right-click the toolbar icon and choose Options (or open it from the popup via Full settings).
  2. Under Custom User-Agent, enter a name and paste your User-Agent string.
  3. Optionally tick Simulate mobile to also send sec-ch-ua-mobile: ?1.
  4. Click Add. The saved profile can now be selected as the global identity or used in a per-site rule.

4. Set a User-Agent for a specific website

  1. Open Options (right-click the icon → Options).
  2. Under Per-site rules, enter a site domain or keyword (for example, example.com or m.example.com).
  3. Choose the identity this site should use, then click Add rule.
  4. All other sites keep the global identity (or Chrome’s default when none is set).

5. Disable or restore the default

  • Pause simulation — open the popup and turn off Simulation on. This stops all User-Agent changes, including per-site rules.
  • Restore default — in the popup, click Restore default. This clears the global identity so Chrome uses its native User-Agent again.

6. Troubleshooting & FAQ

I switched User-Agent but the site looks the same.

Some sites detect devices using Client Hints, real screen size, or cached pages rather than the User-Agent alone. Try a hard refresh, or check whether the site reads Client Hints. Changing the User-Agent does not change every browser fingerprint.

Will this bypass a site’s login or anti-bot checks?

No, and it is not designed to. The extension is for web compatibility and development testing only. It does not guarantee access to any restricted content.

Does the extension collect or send my data?

No. All settings are stored locally in Chrome. See the privacy policy.

How do I delete my saved settings?

Remove the extension at chrome://extensions. This clears all locally saved presets, custom User-Agents and per-site rules.

Does it work in Firefox or Safari?

The current version is built for Chrome (Manifest V3) only.

7. Contact

If you still need help, send a message to llcailabs@gmail.com. Please include the extension version, your Chrome version, the steps you took, and a short description of the issue. Screenshots are welcome.