I'm typesetting a book with keywords in the margin. For doing this, I copy a text frame with the right settings, anchoring them to the connected words in the main text. Works fine. But something happens that I don't understand: an anchor shouldn't take up any space, at least, that seems logical to me. But after inserting the anchor the paragraph is recomposed. Not a big problem here; I fine-tune the paragraphs in a later phase. Still I'd like to know: is this a known bug or is there something wrong with my notion of logic?