I've been watching some VHS tapes I own with movies that have their top and bottom sides opened up from 16:9 to the 4:3 aspect ratio to fit TVs with that aspect ratio.
I've been imagining the top screen of 3DS games (mostly the game mentioned below) getting the open-matte treatment, where the top and bottom sides of the top screen is opened up to fit 4:3 screens.
I'm requesting to add an open-matte feature for Citra, so we can enjoy our 3DS games, including it's non-FMV cutscenes, on 4:3 screens without cropping the left and right sides.
Here's a comparison photo.
Game: Style Savvy - Fashion Forward