[Unit]
Description=inhibit disk automounting
Before=udisks2.service

[Service]
Type=oneshot
RemainAfterExit=yes

ExecStart=mkdir -p /run/udev/rules.d
ExecStart=sh -c "echo 'SUBSYSTEM==\"block\", ENV{UDISKS_IGNORE}=\"1\"' > /run/udev/rules.d/10-udisks-inhibit.rules"
ExecStart=udevadm control --reload
ExecStart=udevadm trigger --subsystem-match=block

ExecStopPost=rm -f /run/udev/rules.d/10-udisks-inhibit.rules
ExecStopPost=udevadm control --reload
ExecStopPost=udevadm trigger --subsystem-match=block

[Install]
WantedBy=graphical.target