Hi Anthony... i have not gone that far yet.. BUT.. Apple gave the idea.. and found this How to set php ignore user abort in Server Connect? - #8 by transcoderm ... seems like transcoderm made it work ...
"*I managed to work around the session locking or synchronous script issues (whatever they are) by using the Fetch API. Instead of using a dynamic event, I use a static event on success/done to call the SA mail API using a JavaScript function. This way, my mail script can run in the background without interfering with the current page." --- transcoderm