On my Thinkpad T480s, the function keys all have icons on them for volume control, brightness, etc. The F11 and F12 keys have a keyboard and favorites icon, but those don't appear to do anything in Ubuntu. I'd like to remap those keys to different functions (for example, show the Activities menu / all open windows). However, I can't remap these keys as normal in keyboard shortcuts, those icon keys don't register when trying to create a shortcut.
How can I remap these keys? I saw this suggestion for debian. Is that the proper solution for Ubuntu 18.04 or is there a better way?