The email text can be edited on the document type. For example, for issued invoice types, go to the given type under the "Texts on document" tab, in the "Text for sending" field.
Unfortunately, the text does not support any formatting — only plain text can be used. The footer "Generated by the ABRA Flexi accounting system" cannot be removed by standard means.
The system attaches a PDF and ISDOC to the email. Unwanted attachments can be removed afterwards in your email client.
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