SoftU2F was previously proposed as a workaround, but it seems to no longer work due to macOS's many security changes in recent years. Does anyone currently have a workaround, or does no such alternative exist?
Also, is there any way the community can help implement this? If I knew how to, I would be happy to do so myself. However, for now, I am left feeling both a bit helpless and a bit hopeless. I wonder why this important feature – which has existed in both Safari and Chrome for years – has been paid such little attention by Mozilla, an organization supposedly committed to advancing privacy & security on the web.