If custom screenshot resolution is set to other than the default values, the resulting screenshot will be incorrect and distorted.
Input image: 1080x1080

Running the image through this shader: https://www.shadertoy.com/view/4sySzw
Outputting it to a 480x360 image:

Expected behaviour: the same as if I change the canvas size in the web version of shadertoy
If custom screenshot resolution is set to other than the default values, the resulting screenshot will be incorrect and distorted.
Input image: 1080x1080

Running the image through this shader: https://www.shadertoy.com/view/4sySzw
Outputting it to a 480x360 image:

Expected behaviour: the same as if I change the canvas size in the web version of shadertoy