I have vaguely heard about how ASD causes people to talk about or say things that can offend people in certain ways, and that the person with ASD often has no clue that they are doing so.

I imagine that the hardest part is noticing when one is saying things or acting offensive to neurotypicals. But if the person realised it, they would not do it and the problem would not even exist in the first place. So everything hinges on being able to notice.

How is this usually remedied?