Comment 20 for bug 1740894

@Sebastien: That's the thing, on the Dell XPS 15 9575 there IS a regression with xkb-data 2.23.1-1ubuntu1.18.10.1.

On this machine, the airplane mode key worked perfectly out-of-the-box (i.e., the key enabled AND disabled the airplane mode) with the development version of Cosmic, using xkb-data 2.23. See my comment #13 further up in this bug.

Here's the debug output for gnome-settings-daemon:

[*** Airplane mode is off, Wifi and BT are on ***]

/usr/lib/gnome-settings-daemon/gsd-rfkill -v
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:16.867: Read killswitch of type 'WLAN' (idx=1): soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:16.867: Read killswitch of type 'BLUETOOTH' (idx=11): soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:16.867: Added rfkill with ID 1
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:16.867: Added Bluetooth rfkill with ID 11
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:17.185: Registered client at path /org/gnome/SessionManager/Client29
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:17.187: Opened rfkill-input inhibitor.

[*** Here I am pressing the airplane mode key to enable Airplane mode > Wifi/BT goes off ***]

(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:26.232: RFKILL event: idx 1 type 1 (WLAN) op 2 (CHANGE) soft 1 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:26.232: Changed rfkill with ID 1
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:26.352: RFKILL event: idx 11 type 2 (BLUETOOTH) op 2 (CHANGE) soft 1 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:01:26.353: Changed Bluetooth rfkill with ID 11

[*** Here I am pressing the airplane mode key again to DISable Airplane mode > Wifi/BT should go back on. This fails and the airplane mode re-engages immediately as described ***]

(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:11.523: RFKILL event: idx 1 type 1 (WLAN) op 2 (CHANGE) soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:11.523: RFKILL event: idx 11 type 2 (BLUETOOTH) op 2 (CHANGE) soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:11.523: Changed rfkill with ID 1
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:11.523: Changed Bluetooth rfkill with ID 11
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:12.394: RFKILL event: idx 1 type 1 (WLAN) op 2 (CHANGE) soft 1 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:12.394: Changed rfkill with ID 1
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:12.394: RFKILL event: idx 11 type 2 (BLUETOOTH) op 2 (CHANGE) soft 1 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:03:12.394: Changed Bluetooth rfkill with ID 11

[*** Here I am pressing DISabling Airplane mode from the Gnome panel menu > Wifi/BT goes back on. This works ***]

(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:05:10.298: RFKILL event: idx 1 type 1 (WLAN) op 2 (CHANGE) soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:05:10.298: RFKILL event: idx 11 type 2 (BLUETOOTH) op 2 (CHANGE) soft 0 hard 0
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:05:10.298: Changed rfkill with ID 1
(gsd-rfkill:18272): rfkill-plugin-DEBUG: 19:05:10.298: Changed Bluetooth rfkill with ID 11