paidPartial email trigger

[pavlenex]

Discussed in #5920

^{Originally posted by earlingeling April 9, 2024}
Sometimes customers pay insufficient funds and get their invoice marked as New (paidPartial).

The reasoning varies - if they use large crypto-exchanges like binance, coinbase and similar, they often take a rather high fee. Also, they might also take their flat btc fee out of the receivers end of the transaction.

To remedy these situations it would be really helpful to be able to automatically trigger an email rule for paidPartial.
Then the store can give in-depth instructions on how this happens and how they can solve it themselv - and largely remove customers enquiries about paidPartial invoices.

Also, an {Invoice.url} link to their invoice would be helpful so we can link them back to their invoice (especially for stores with modal btcpay overlays at checkout)

[dstrukt]

ACK