I did a little research. Apparently, “Chinotto” is a dwarf bitter orange.
I popped open a Chinotto drink just now because I decided it was time.
I just figured out where Sanbittèr gets its primary flavor.
The thing is, Sanbittèr is a very much distilled-down, strong version of Chinotto. I don’t mind Chinotto so much (though I’m not going to get any more; I’ll stick to Limonata), but Sanbittèr is kind of icky.