Juggling With Eggs on Nostr: I needed to know how to formally address a non-binary person today in terms of ...

I needed to know how to formally address a non-binary person today in terms of writing their name and postal address.

My child told me it’s Mx. Pronounced ‘mix’.

I then looked it up and realised this non-binary equivalent of Mr/Mrs/Miss/Ms has been in usage since the 1970’s, before I was born.

I felt very ignorant.

Can I just check regarding usage and whether there are any other widely used alternatives in #NonBinary community?