Microsoft Ergonomic Keyboard the 2019 model (not the old one 4000 model) generates several keystrokes for the new keys. It is well known how to remap the Zoom slider of the old version however the question is how to do that for the new keys. The udev rules allow to specify only one scancode for a mapping entry, for example KEYBOARD_KEY_0c022d=pageup.
Here is an output of evtest for the Office key:
Event: time 1604142043.024827, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e0
Event: time 1604142043.024827, type 1 (EV_KEY), code 29 (KEY_LEFTCTRL), value 1
Event: time 1604142043.024827, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e1
Event: time 1604142043.024827, type 1 (EV_KEY), code 42 (KEY_LEFTSHIFT), value 1
Event: time 1604142043.024827, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e2
Event: time 1604142043.024827, type 1 (EV_KEY), code 56 (KEY_LEFTALT), value 1
Event: time 1604142043.024827, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e3
Event: time 1604142043.024827, type 1 (EV_KEY), code 125 (KEY_LEFTMETA), value 1
and here for the Emoji key:
Event: time 1604142174.537667, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e0
Event: time 1604142174.537667, type 1 (EV_KEY), code 29 (KEY_LEFTCTRL), value 1
Event: time 1604142174.537667, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e1
Event: time 1604142174.537667, type 1 (EV_KEY), code 42 (KEY_LEFTSHIFT), value 1
Event: time 1604142174.537667, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e2
Event: time 1604142174.537667, type 1 (EV_KEY), code 56 (KEY_LEFTALT), value 1
Event: time 1604142174.537667, type 4 (EV_MSC), code 4 (MSC_SCAN), value 700e3
Event: time 1604142174.537667, type 1 (EV_KEY), code 125 (KEY_LEFTMETA), value 1
Event: time 1604142174.537667, -------------- SYN_REPORT ------------
Event: time 1604142174.545449, type 4 (EV_MSC), code 4 (MSC_SCAN), value 7002c
Event: time 1604142174.545449, type 1 (EV_KEY), code 57 (KEY_SPACE), value 1
So the Office key generates only the modifiers keystrokes and the Emoji key generates the modifiers keystrokes and the space keystroke after about 8 milliseconds. There are also other new custom keys on that keyboard which generate servers keystrokes, however the Office and Emoji keys are most important to remap because of their location.
