UltraWide Monitor Problems

So I have a UltraWide 21:9 monitor (2 actually).
Im using a Skin called FTV (Fred Edition) which is designed only for 16:9 – now I can bare using it with its slight stretch but it would be nice to use it with proper compatability for 21:9 mainly because when its stretched the Poster sizes on the Widgets tend to make it more square so it hides some of the image and most of the time hiding so much that I cant even see the title.

Is it possible to run the UI of Kodi in 16:9, but when a video is playing make the video the full size of the monitor 21:9 which will only stretch out if the video’s aspect ratio itself should be stretched. Lets say its playing a 16:9 video – dont stretch it but if its playing a 21:9 video then stretch it. You know?