UI with rectangles? Don't use null as a source!
Create a 1x1 square image and add it to your sprite atlas. That way all rectangles will be drawn together with the images. You can reduce several draw calls per frame!
When using a null reference in an Image field: "None (Sprite)", Unity actually puts a UnityWhite texture in there that causes the GPU to make an additional draw call.

https://twitter.com/HetiDev/status/1493317817688629252

#ui #optimization #tips