@WannesMalfait Ha good. I think I remember that at the time when Blender had the 10 layers mapped to 1-9 (and 0) Qwerty keys, it was difficult for me to do things like Shift+these keys to activate the visibility of multiple layers. But I'm not sure if this souvenir is really something that existed or something that my memory mash-up from various experiences. It was long ago :)
So, yes 1-9 are often remapped for other keyboards, but trouble starts with modifier + them, afair.