Spoofs the browser's user agent during u2f authentication, to allow it to be used on sites that disable security key u2f, based on user agent.

What is u2f-useragent-adapter?

u2f-useragent-adapter is a Firefox add-on that spoofs the browser's user agent during u2f authentication. It allows the use of u2f hardware security keys on websites that disable them based on the user agent, such as Facebook. By pretending to be using a Chrome browser, the add-on bypasses the restriction and enables the normal use of security keys.

Users: 445 ▼ -2
Rating: 5.00 (1)
Version: 1.0 (Last updated: 2019-03-16)
Creation date: 2019-03-16
Weekly download count: 11
Firefox on Android: No
Risk impact: High risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
  • webRequest
  • webRequestBlocking
  • https://www.facebook.com/checkpoint/*
Size: 7.66K
URLs: Website
Stats date:

Other platforms

Not available on Chrome
Not available on Edge
Want to check extension ranking and stats more quickly for other Firefox add-ons? Install Chrome-Stats extension to view Chrome-Stats data as you browse the Firefox Browser Add-ons.
Chrome-Stats extension

u2f hardware security keys, like the Yubikey, add a second layer of authentication when you log in on websites. The Firefox and Chrome browsers both support these security keys, but some websites like Facebook check the browser's user agent, and don't allow them to be used when logging in using browsers other than Chrome (they will instead ask for alternative second factor methods, like TOTP). By pretending to be using a Chrome browser during the login, it is possible to get around that restriction, and use the security key as usual.

Risk impact

u2f-useragent-adapter is risky to use as it requires a number of sensitive permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install u2f-useragent-adapter if you trust the publisher.

Risk likelihood

u2f-useragent-adapter has earned a fairly good reputation and likely can be trusted.

Upgrade to see risk analysis details