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This idea has been merged into another idea. To comment or vote on this idea, please visit MXM-I-498 Add an attachment to MXInvoice.
In cases where there is a directional agreement between two or more accounts, it would be great to have an attachment feature where the invoice can be attached for all parties to see as some invoices might contain multiple items. Attaching an invoice would be especially helpful in many cases other than that as well.