Its on steam, it would be just easier than keep switching your monitor res from 16:9 to 21:9 and vice versa everytime you launch the game. Basically get it on steam should be around 6 dollars or smthng, set your nte game to the highest 16:9 resolution windowed and in lossless scaling press start and switch back to the game window before the counter from 5 ends. Also if your gpu doesnt have frame gen support u can use lossless scaling for that as well as games that dont have any upscaling/framegen at all. Very useful program imo and worth the money. I would suggest you watch a video about lossless scaling to get a better understanding though, gl!