After further looking into the xero system we spotted a flaw with this idea. It launched the invoice on an online responsive page however if your invoices had any more than a few words of text it made a mess of the whole thing. We scrapped the idea. The accept button is a good idea but only if it was actually on the pdf like the pay online button is.
Also in the exact same position. Have a trial with Xero mainly for this feature. This would be superb if this could be included.
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