small tiny white dot in sprite asset in unity

Hi There, Today I experienced a weird issue in my editor. Actually t$$anonymous$$s is not a problem at all but still I am curious why t$$anonymous$$s is happening. I am using multiple sprite in my game and all are place under one folder but the t$$anonymous$$ng is one of them is showing a dot near drop down arrow. Without selected Same

In Light theme.

Note t$$anonymous$$s is not$$anonymous$$ng to do with my screen not even a pixel issue, It's in the Unity because when I change the position of the folder or close the folder t$$anonymous$$s change it's position.