Handling of long footnotes could be improved in at least three ways:

1. Sometimes a footnote absolutely cannot start on the same page as its reference either because the given footnote follows so closely behind a very long footnote (or a dense cluster of shorter footnotes). Presently, InDesign simply stops setting text at that point, as it would when a hits a word it cannot fit into any subsequent frame in the story. Ideally such footnotes would be not only be permitted but be custom-labelable—e.g. “(from p. 17)”—but for now simply permitting such footnotes, elegantly or not, would be a far less disruptive behavior.
2. Presently very long footnotes will occupy all but one line of subsequent frames for as many frames as they require, and this often has the effect of making the one line of main text appear to be a heading for the footnote. It would be nice to be able to customize the amount of a text frame allocated to footnotes. This value could be set either as a minimum number of lines or a minimum percentage of the frame height reserved for the main text. (Fallback request: If customization isn’t easy to implement, changing the fixed minimum to 3 lines would be a huge improvement over 1 line.)
3. Historically, long footnotes that continue onto a subsequent page have often been specifically labeled—e.g., “vii (cont’d)”—but InDesign does not presently support such labeling. It would be beneficial if there were an option to apply custom text applied to continued footnotes.