New email field in Notifications to pull from metadata

[stevejburge]

Is it possible to add a "custom email" input field inside "who to notify" in "notifications"? It would be great if I can manually specify an email address or reference a user metadata field for it to read from.

For our scenario, I have a user metadata field called "editor", and we fill this in with a specific user (let's say Frank). I want to be able to notify Frank when status changes, but currently, in order to do this, I have to add him in the "notifications box" inside a post. It would be great, if i can just use [psppno_post meta:_pp_editorial_meta_text_editor] in a "send to" input field.