The Chrome Webview used by Franz isn't able to make the appropriate API calls to the USB controller to detect and interact with the two-factor security key
Franz should be able to interact with the two-factor key
On the two step page of logging in, the message "Something went wrong. Remove your Security Key and try again" appears.

Whether for personal security or a corporate security policy, it would be beneficial to support these usb two-factor devices.
There is a discussion about this in the electron issue tracker: https://github.com/electron/electron/issues/3226
With the latest comments there, it seems like that progress has been made. I will try to get one of those keys to do my research.
Has support for U2F keys been added in the meantime @adlk?
Nope but I have changed the stablebot config to exclude "feature requests"
Thanks @adlk, would love to see it happen :)
There seems to be progress on this topic with electron 4. Migrating Franz to electron 4.x however is just a very bumpy ride that takes time and requires a long testing cycle. But let's hope for the best.
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There seems to be progress on this topic with electron 4. Migrating Franz to electron 4.x however is just a very bumpy ride that takes time and requires a long testing cycle. But let's hope for the best.