Usually these are post-it notes. You can heat it with a hair dryer and peel it off.

Yes, because the supplementary provisions are on the surface for a long time, it will make the color retreat to the surface. This can only be scrubbed with toothpaste.

Because there is a friction agent in toothpaste (now the friction agent of toothpaste is generally white carbon black), it can remove tiny traces on the surface without causing too much damage to the surface.