Fix Magic Mouse (1 but may work on 2 as well) on Arch Linux

fixmagicmouse.sh

# Stop the kernel driver
sudo modprobe -r hid_magicmouse
# Start the driver with these options
sudo modprobe hid_magicmouse \
        emulate_3button=0 \
        middle_click_3finger=1 \
        stop_scroll_while_moving=1 \
        scroll_acceleration=1 \
        scroll_speed=50 \
        scroll_delay_pos_x=300 \
        scroll_delay_pos_y=300
# You can save it for persistance in /etc/modprobe/hid_magicmouse.conf:
# option hid_magicmouse emulate_3button=0 middle_click_3finger=1 stop_scroll_while_moving=1 scroll_acceleration=1 scroll_speed=50 scroll_delay_pos_x=300 scroll_delay_pos_y=300