Any way to request read receipt on the nlapiSendEmail action? Or the only way is to add beforeLoad function to the message record?

Deploy it to the message record

The problem with that is that it will have no influence on emails sent via scripts using the nlapisendemail api.

There is no way to make a script trigger if the emails are sent via api to my knowledge

I know that, that's why I asked if there is a way to request read receipt while using the nlapisendemail api. Guess not... I'll try to open a ticket with NetSuite support, maybe they will have an idea. Anyhow, thanks for your help.