Not in the future, no, they're supported now
That said, resolution
height determines your font size, and that's a pretty wide aspect ratio! So it'll be using the size 18 font, and your map view will end up showing a fairly wide area.
You can see what the different fonts and resolutions look like on
this page. (Right now there are players using 3840x2160.) And while I don't have a sample up for 21:9, you can see the 1920x1080 sample and imagine the map view (and top) simply showing a wider area. An extra 640 pixels would mean about 35 extra columns for the map display.
...
Eh, what the heck, I threw together a
(very quick and dirty) mockup for you in the right resolution by editing the 1920x1080 image
. Open that up at full size on your screen and that's about what it will look like.
