Why don't I see my Garmin watch in the "target platforms" list?

I have a Vivoactive 3 Music and I'd like to target it for a widget I'm developing, but it's not in the list of options under "supported devices".  Why don't I see it? Is there still a way to target it?

Edit:

The Vivoactive 3 Music is not merely grayed out.  It doesn't appear at all.  And it seems to be the same even if try building a watch face instead.  I do see other devices (some Fenixes, Forerunners, Venus, etc.), some grayed and some not (though some like the Forerunner 55 are grayed out when I expect them not to be, but I suspect that's a different issue).