where did my kodi button go

[dishuser]

Take your old remote(with the Kodi button), and point it at the new Remote.
Do the setup to learn, using the "Source" button on new remote, then press and hold the Kodi button on old remote, until learn is completed.
Now pack away the old remote.

I'll give it a try later with my other air mouse remote
I currently have source set up for tv inputs