Sometimes when writing, I forget the er when referring to a person who stutters (pws). So sometimes I would accidentally write something like "There are many stutters" when I meant to write "There are many stutterers". It's only when I proof read that I can catch the mistake and correct it. So don't get too hung up on it. Many of times people make mistakes when they type. What matters is that the point gets across. You can usually infer what they mean by the context.