I recently got an Apple's Magic Trackpad. I paired it with Ubuntu 18.04.2 LTS and worked out of the box, no special drivers needed.

However, I experience frequent disconnections that last a few seconds (5-15 seconds usually), which are quite annoying, as the cursor stops responding during that interval. The trackpad connects by itself after that period. That usually happens every 20-40 minutes.

I use the onboard bluetooth device of my laptop. I also have, at the same time, two more bluetooth devices (keyboard and mouse) and they do not experience that issue, just the trackpad. On ocassion I use bluetooth headphones which work just fine.

First of all: 

Using the command `bluetoothctl` I get the following every time I experience a disconnection:

`[CHG] Device F4:1B:A1:33:F9:8D Connected: no
[CHG] Device F4:1B:A1:33:F9:8D Connected: yes`

Checking `dmesg` I can see more information: (if I am not mistaken, this shows 4 disconnections)

`
[ 1609.070538] magicmouse 0005:05AC:030E.0007: unknown main item tag 0x0
[ 1609.070797] input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0007/input/input23
[ 1609.071460] magicmouse 0005:05AC:030E.0007: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
[ 1676.917377] NET: Registered protocol family 38
[ 1872.815348] magicmouse 0005:05AC:030E.0008: unknown main item tag 0x0
[ 1872.815559] input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0008/input/input24
[ 1872.816248] magicmouse 0005:05AC:030E.0008: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
[ 3101.682671] magicmouse 0005:05AC:030E.0009: unknown main item tag 0x0
[ 3101.683100] input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009/input/input25
[ 3101.683673] magicmouse 0005:05AC:030E.0009: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
[ 3110.683360] magicmouse 0005:05AC:030E.000A: unknown main item tag 0x0
[ 3110.683929] input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:1024/0005:05AC:030E.000A/input/input26
[ 3110.684487] magicmouse 0005:05AC:030E.000A: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
`

And this is what journalctl -b shows at the moment of the disconnection/reconnection:

`de juny 13 21:37:49 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: removing device Apple Wireless Trackpad
de juny 13 21:37:49 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "fd" "64" (1,63 m)˜ 
de juny 13 21:37:49 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device removed
de juny 13 21:37:49 TM1703 gnome-shell[5071]: g_array_unref: assertion 'array' failed
de juny 13 21:37:49 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) UnloadModule: "libinput"
de juny 13 21:37:49 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) systemd-logind: releasing fd for 13:80
de juny 13 21:37:49 TM1703 upowerd[1271]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0008
de juny 13 21:37:50 TM1703 kernel: magicmouse 0005:05AC:030E.0009: unknown main item tag 0x0
de juny 13 21:37:50 TM1703 kernel: input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009/input/input25
de juny 13 21:37:50 TM1703 kernel: magicmouse 0005:05AC:030E.0009: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: Adding input device Apple Wireless Trackpad (/dev/input/mouse1)
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) No input driver specified, ignoring this device.
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) This device may have been added with another device file.
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: Adding input device Apple Wireless Trackpad (/dev/input/event16)
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: Applying InputClass "libinput touchpad catchall"
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) Using input driver 'libinput' for 'Apple Wireless Trackpad'
de juny 13 21:37:50 TM1703 upowerd[1271]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) systemd-logind: got fd for /dev/input/event16 13:80 fd 65 paused 0
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: always reports core events
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "Device" "/dev/input/event16" (40,64 cm)˜ 
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "_source" "server/udev"
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: is tagged by udev as: Touchpad
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device is a touchpad
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device removed
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "config_info" "udev:/sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009/input/i
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) XINPUT: Adding extended input device "Apple Wireless Trackpad" (type: TOUCHPAD, id 11)
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "AccelerationScheme" "none"
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) selected scheme none/0
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) acceleration factor: 2.000
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) acceleration threshold: 4
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: is tagged by udev as: Touchpad
de juny 13 21:37:50 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device is a touchpad
de juny 13 21:37:51 TM1703 upowerd[1271]: treating change event as add on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009/power_supply/hid-f4:1b:a1:3
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: removing device Apple Wireless Trackpad
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "fd" "65" (1,65 m)˜ 
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device removed
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) UnloadModule: "libinput"
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) systemd-logind: releasing fd for 13:80
de juny 13 21:37:59 TM1703 gnome-shell[5071]: g_array_unref: assertion 'array' failed
de juny 13 21:37:59 TM1703 upowerd[1271]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:030E.0009
de juny 13 21:37:59 TM1703 kernel: magicmouse 0005:05AC:030E.000A: unknown main item tag 0x0
de juny 13 21:37:59 TM1703 kernel: input: Apple Wireless Trackpad as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:1024/0005:05AC:030E.000A/input/input26
de juny 13 21:37:59 TM1703 kernel: magicmouse 0005:05AC:030E.000A: input,hidraw1: BLUETOOTH HID v1.60 Mouse [Apple Wireless Trackpad] on 64:5d:86:86:3f:98
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: Adding input device Apple Wireless Trackpad (/dev/input/mouse1)
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) No input driver specified, ignoring this device.
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) This device may have been added with another device file.
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) config/udev: Adding input device Apple Wireless Trackpad (/dev/input/event16)
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: Applying InputClass "libinput touchpad catchall"
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) Using input driver 'libinput' for 'Apple Wireless Trackpad'
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) systemd-logind: got fd for /dev/input/event16 13:80 fd 65 paused 0
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: always reports core events
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "Device" "/dev/input/event16" (40,64 cm)˜ 
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "_source" "server/udev"
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: is tagged by udev as: Touchpad
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device is a touchpad
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device removed
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "config_info" "udev:/sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:1024/0005:05AC:030E.000A/input/
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) XINPUT: Adding extended input device "Apple Wireless Trackpad" (type: TOUCHPAD, id 11)
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Option "AccelerationScheme" "none"
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) selected scheme none/0
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) acceleration factor: 2.000
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (**) Apple Wireless Trackpad: (accel) acceleration threshold: 4
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: is tagged by udev as: Touchpad
de juny 13 21:37:59 TM1703 /usr/lib/gdm3/gdm-x-session[4882]: (II) event16 - Apple Wireless Trackpad: device is a touchpad
de juny 13 21:37:59 TM1703 upowerd[1271]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:1024/0005:05AC:030E.000A
de juny 13 21:38:00 TM1703 upowerd[1271]: treating change event as add on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:1024/0005:05AC:030E.000A/power_supply/hid-f4:1b:a1:
lines 6761-6814/6814 (END)
`

In case it is useful, I am using blueman 2.0.5-1ubuntu1 and libinput-bin 1.10.4-1