Accidentally, I found that the display problem was related to the
material shader. The default sprite renderer material's blend mode is
additive. it needs to change to others like transparent or Mask or
something else. Create a new material and chang...
Thanks amx95! This Solves my problem. For everyone who encountered the
same situation, that setting pass is Project setting - Engine -
Rendering - Postprocessing - Enable alpha channel support in post
processing - Allow Through ToneMapper
