in mobile app, have a color banner to indicate an invoice has been
When using the mobile app, currently once an invoice has been completed and emailed, it says "unpaid invoice" in a blue banner at the top. It is sometimes difficult to notice the little popup which says "invoice sent" at the bottom, and this could lead to the invoice being sent again.
Changing the color of the banner at the top (i.e. to green) would be a nice visual indicator the email has already been sent.

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