I'm not a fan of the use of microagression as a word, but this just seems like normal behavior to me. Like people finishing my words for me. If I counted everytime that happened during one day I'd get to like 200 at least. And I don't blame people for doing it, most of it comes from a genuine desire to help when they see stutterers struggling to say something, and I can't really hold that against people. I always thought microagression referred to like small instances of racism or other discriminatory practices like "you don't look like x race" as a way of saying someone is attractive or whatever. Or "you speak well for a person from X place". None of that comes from a genuine desire to help. Either way I prefer using a different word since microagression is such a broad term that it barely means anything now.