I have been trying to find a way to use the `<keygen>` tag in production for a very long time, but I am consistently thwarted by the browsers simply not support

I have been trying to find a way to use the `<keygen>` tag in production for a very long time, but I am consistently thwarted by the browsers simply not supporting it well enough. Where does the generated private key go? How do I sign things with it again? It's never clear, and browser support is terribly inconsistent.