I have a condition that affects circulation to my fingers and lately I've been wanting something warmer than gloves with liners for biking. The solution seems to be something called "index finger mittens." They're just mittens with a separate index finger for a trigger or brake lever.
I live far enough south that I've never seen or heard of these things. Apparently they might also be called one of the following: split-finger mittens 3 finger mittens/gloves lobster mittens/gloves trigger finger mittens
Since I live in a county with only two paved roads I have the usual problem of no in-person shopping options and reduced options online. Amazon stopped honoring their "free returns" out here a little over a year ago. I stopped shopping there rather than pay UPS for a pickup every time I have a problem with an item.
I didn't see good options on walmart or temu. Aliexpress has a handful of options but I worry about quality with that site, and they're still more like snowboarding mittens than biking mittens.
(EDIT: after a 2nd look at the options on aliexpress it turns out these are the only ones that would fit me: https://www.aliexpress.us/item/2255800334665556.html size medium)