U2F support in Tor
is it possible to enable U2F authentication in the Tor Browser?
I know this has been discussed in the past but there has been some progress on the Firefox side since then, as Firefox now supports U2F by default (so filing this under "bug" rather than "feature request"). However I wasn't able to get it to work in the Tor Browser. It simple doesn't pick up the device when I plug it in; the device is supposed to flash but doesn't do anything; pressing the button doesn't allow to authenticate. The yubikeys I tested with (Neo and 5) work fine for challenge-response with KeepassXC however.
What I've tried so far:
(based on the previous thread):
-downloaded the 70-u2f.rules to udev/rules.d and ran sudo udevm control --reload-rules
-enabled the 4 security.webauth* lines (u2f, webauthn, enable usbtoken and enable softtoken - not sure the last one is relevant) in the tor browser config (about:config).