The P3 toys are a joy and you can go on finding additional ones long after you first get the car!
I can't find which model you have but on the V and XC 70's it is possible to fit a plug-in module in the OBD2 socket that allows you to not only open the tailgate but also to0 close it from both the dashboard button and the remote. It doesn't really make a huge difference but it's just great to be able to do it.
https://www.volvoforums.org.uk/showthread.php?t=296675 covers the details of the latest unit. The only current problem is that Evgeny in a Russian and I don't know if the current Russia/Ukraine situation will inhibit his ability to supply this item.