I noticed that the file /etc/udev/rules.d/70-snap.firefox.rules does not have any rules for the Trezor devices.
In my Trezor rules file, /etc/udev/rules.d/51-trezor.rules, that can be downloaded from https://data.trezor.io/udev/51-trezor.rules, I appended the FireFox snap TAG to one of the existing lines to get, for example: KERNEL=="hidraw*", ATTRS{idVendor}=="1209", ATTRS{idProduct}=="53c1", MODE="0660", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl", TAG+="snap_firefox_firefox" Unplug/replug the device and then try again in FireFox. That worked for me. So, the fix is probably for FireFox to include the Trezor U2F device configs in whatever winds up generating /etc/udev/rules.d/70-snap.firefox.rules -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1947746 Title: [Snap] Ubuntu Firefox installed from snap cannot use Trezor U2F Status in firefox package in Ubuntu: New Bug description: Trezor U2F security key doesn't work with firefox snap after updating to Ubuntu 21.10, but works with apt debian firefox package. Steps to reproduce: 1) Insert Trezor U2F security key in USB port. 2) Launch `run snap firefox` (it is the default on Ubuntu 21.10) 3) Test https://demo.yubico.com/webauthn-technical/registration It works well on Ubuntu 21.04 and on traditional apt debian installation. $ snap list firefox Name Version Rev Tracking Publisher Notes firefox 93.0-1 631 latest/stable mozillaâś“ - $ snap connections firefox Interface Plug Slot Notes audio-playback firefox:audio-playback :audio-playback - audio-record firefox:audio-record :audio-record - avahi-observe firefox:avahi-observe :avahi-observe - browser-support firefox:browser-sandbox :browser-support - camera firefox:camera :camera - content[gnome-3-38-2004] firefox:gnome-3-38-2004 gnome-3-38-2004:gnome-3-38-2004 - content[gtk-3-themes] firefox:gtk-3-themes gtk-common-themes:gtk-3-themes - content[icon-themes] firefox:icon-themes gtk-common-themes:icon-themes - content[sound-themes] firefox:sound-themes gtk-common-themes:sound-themes - cups-control firefox:cups-control :cups-control - dbus - firefox:dbus-daemon - desktop firefox:desktop :desktop - desktop-legacy firefox:desktop-legacy :desktop-legacy - gsettings firefox:gsettings :gsettings - hardware-observe firefox:hardware-observe :hardware-observe - home firefox:home :home - joystick firefox:joystick - - mpris - firefox:mpris - network firefox:network :network - network-observe firefox:network-observe - - opengl firefox:opengl :opengl - personal-files firefox:dot-mozilla-firefox :personal-files - removable-media firefox:removable-media :removable-media - screen-inhibit-control firefox:screen-inhibit-control :screen-inhibit-control - system-files firefox:etc-firefox-policies :system-files - system-packages-doc firefox:system-packages-doc :system-packages-doc - u2f-devices firefox:u2f-devices :u2f-devices - unity7 firefox:unity7 :unity7 - upower-observe firefox:upower-observe :upower-observe - wayland firefox:wayland :wayland - x11 firefox:x11 :x11 - $ cat /etc/os-release PRETTY_NAME="Ubuntu 21.10" NAME="Ubuntu" VERSION_ID="21.10" VERSION="21.10 (Impish Indri)" VERSION_CODENAME=impish ID=ubuntu ID_LIKE=debian HOME_URL="https://www.ubuntu.com/" SUPPORT_URL="https://help.ubuntu.com/" BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/" PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy" UBUNTU_CODENAME=impish $ echo $XDG_SESSION_TYPE wayland $ uname -r 5.13.0-19-generic To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1947746/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp