Ah fantastic! Not often you need something and exactly that thing exists.

On that topic (and while I've got your useful brain) some clients like Primal force you to have a Nostr username (the @one, not the display name) that contains no spaces. It won't let you save a profile update if you add a space to the username.

Other clients like Damus allow spaces. And you can quasi-hack Primal by adding a space in to the username in Damus and then coming back to Primal—the one with the space will have been updated in Primal.

Is there any sort of convention evolving there? Space, no space?