Comment 36 for bug 1766825

Cyrus Lien (cyruslien)'s solution works.

Just put a executable script of any name in /lib/systemd/system-sleep/.

#!/bin/sh

if [ "$1" = "pre" ]; then
  systemctl stop bluetooth && rmmod btusb
elif [ "$1" = "post" ]; then
  modprobe btusb && systemctl start bluetooth
fi