Why does firefox ask for me to "insert my security USB key?" I have never heard of this.
I'm using metamask and there's a website I can't access because my recently (hours ago) installed windows 10 is saying Mozilla is asking for my USB Security Key. I installed this last night... Obviously I have no such key.
Wšě wotmołwy (1)
It sounds that you access a website that has enabled Two Factor authentication (2FA) or Universal 2nd Factor authentication (U2F) that requires to enter an additional security code. Metamask might be using this feature and in that case you need to check their FAQ pages and their support.