when auto-filling additional to:/cc: addresses, list same-domain addresses first:

- if you start an email addressed to "bob@domain.com", then go to add another email address and start typing "jo" it should list other addresses in the same domain such as "john@domain.com" and "jorge@domain.com" BEFORE addresses at other domains like "joe@anotherdomain.com" even if you otherwise email "joe@anotherdomain.com" far more often.

Think of it like the "I don't always drink beer, but when I do..." commercial:

"I don't always email bob@domain.com, but when I do, I probably want to email john & jorge@domain.com too (but not anyone at anotherdomain.com!)"

this will not only help the user find the email addresses they most likely want faster, but also help prevent the embarrassing and potentially devastating accident of including the wrong email address.