User-Agent Switcher and Manager
Spoof websites trying to gather information about your web navigation—like your browser type and operating system—to deliver distinct content you may not want.
User-Agent Switcher and Manager: Customize Your Browser Identity
'User-Agent Switcher and Manager' is a Firefox extension that facilitates privacy and customization of user experience. It allows you to alter your browser's 'user-agent' string, making it difficult for websites to gather specifics about your browsing setup. This tool is particularly handy for controlling the content that websites deliver to you, based on your apparent operating system or device type. From accelerating loading speeds by indicating a mobile device, to improving privacy by randomizing your user-agent string, this add-on is a powerful tool for modern internet users.
Add-on stats
Weekly download count: 6,621
Firefox on Android: No
Risk impact: High risk impact 
Risk likelihood:
Manifest version: 2
Permissions:
- storage
- <all_urls>
- webNavigation
- webRequest
- webRequestBlocking
- contextMenus
Size: 771.24K
URLs: Website
Ranking
# 222 ▲ 1
Other platforms
Not available on Android
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Add-on summary
Usage example: You can alter your user-agent string to indicate you’re on a mobile device if you prefer seeing mobile versions of sites so they load quicker.
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This extension allows you to spoof your browser "user-agent" string to a custom designation, making it impossible for websites to know specific details about your browsing arrangement.
Overviews: https://www.youtube.com/watch?v=-aVFxvF3N_E https://www.youtube.com/watch?v=4M6_Zc4o1MQ
Notes:
- You can easily set custom "user-agent" strings from the toolbar popup
- The extension uses a two-factor technique to mimic your default "user-agent" string, which is the most reliable method
- The extension does not use any resources when it is not spoofing the user-agent
- The extension enables user-agent spoofing on specific domains only; it is conversely possible to exclude certain domains from spoofing. Check the Options page for more info.
User reviews
These summaries are automatically generated weekly using AI based on recent user reviews.
Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate,
spammy, or outdated. Pros
- Makes YouTube work better with Firefox and uBlock Origin without slowing down performance
- Fixes playback issues on YouTube
- Simple installation for some users (if instructions are followed)
Cons
- Whitelist feature does not work as expected
- Not functioning or lacks updates
- Confusing UI and long English text in settings
- Considered by some as abandonware
Most mentioned
- Not working as intended
- Whitelist feature fails
- User interface issues
- Performance improvement when used correctly
User reviews
by Firefox user 13724807, 2025-01-16
by Firefox user 18447184, 2025-01-06
Perfect extension that does exactly what it's supposed to do and what I need it to do, which is make YT work with FF and UBO without grossly slowing down actions due to Google's anti-competitive tomfoolery.
Unsure why so many people rate it so low. I assume they can't follow simple instructions to set it up or just didn't restart browsers after installed.
by Firefox user 18765963, 2025-01-05
Add-on safety
Risk impact
User-Agent Switcher and Manager requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.
Risk likelihood
User-Agent Switcher and Manager has earned a good reputation and can be trusted.
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