The normalized grid size that the canvas will split the renderable area into.
During rendering the canvas splits the renderable area (bounds of all UI elements) into a grid. This is the normalized size of that grid. For example if you have a renderable area of 100 units with a sortingGridNormalizedSize of 0.1f then each grid cell would be 10 units.
Note: a value of 0 will default to 0.1f.