You may be interested to know that Nitrokey Fido U2F fails to login starting with Chrome 73 (now beta). LED is not flashing and the request eventually reaches a timeout.
This is due to a new feature they call WebAuthenticationProxyCryptotoken. One can login only if chrome is run with --disable-features=WebAuthenticationProxyCryptotoken flag.
See 935131 - chromium - An open-source project to help move the web forward. - Monorail for more info.
This issue still persists in 73.0 the official build of chrome (on Windows 10). Your fix should be listed on https://www.nitrokey.com/documentation/installation#p:nitrokey-fido-u2f&os:windows .
@4mr.minj do you know what WebAuthenticationProxyCryptotoken does? Is this a security relevant feature in the context of the u2f nitrokey? Can I disable it without concerns?
Not really no. My googlefu only lead me as far CryptotokenPrivateCanProxyToWebAuthnFunction function in chromium. This looks like some new input sanitation stuff in the standard: https://community.brave.com/t/yubikey-fails-after-update/44807/2
As far as I can tell the commit has not reached any release branches yet, but their infrastructure is confusing as hell since they switched from google code and I am not one to clone their gigantic repo to check.
It does not seem that important to me, especially since this is a new development. But you are free to read the linked spec documentation in brave forum and tell us 
This should be fixed with a patch since version 74.0.3725.0
Can you retest? It works for me on Linux with Chromium.
Sorry for the long unresponsiveness.
Confirmed
