Make it harder to be tracked on the internet. This is like a user agent randomizer, except that each domain is assigned the same random user agent each time the browser starts up. This will not randomly log you out of sites.

Janus User Agent Firefox Add-On
Janus User Agent is a Firefox add-on that enhances privacy by assigning a random user agent to each domain on browser startup. It helps to make it harder for you to be tracked on the internet without logging you out of sites.
Add-on stats
Manifest V2
Rating: 4.67
(3)
Weekly download count: 3
Firefox on Android: Yes
Permissions:
- <all_urls>
- webRequest
- webRequestBlocking
Size: 22.09K
Other platforms
Not available on Chrome
Not available on Android
Not available on Edge
User reviews
Very simple extension, does exactly what it says and nothing more. If you don't believe me, audit the code yourself. My only complaint is the lack of a whitelist.
by geeknik, 2019-12-03
Compatible with Waterfox! This add-on has absolutely no options, no icons, nothing! It works completely automatic, selecting a random agent string for each domain visited by the user. Unfortunately, there is no way to select/edit available agent strings, whitelist/blacklist domains or anything at all.
by Cyberknight, 2019-05-11
It seems to work, but on some sites such as addons.mozilla.org, it says I require newer version of firefox to use a certain addon. This addon would be even better if it also allows custom agent selection to avoid problems like these.
by Bill, 2019-03-26
Add-on safety
Risk impact
Janus User Agent requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.
Risk impact analysis details
- Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
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Risk likelihood
Janus User Agent has earned a fairly good reputation and likely can be trusted.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
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