message: Fix error in ProseMirror example
diff: @@ -88,7 +88,7 @@ export class FootnoteView {
  for (const transaction of transactions) {
  for (const step of transaction.steps) {
  - outerTr.step(step).map(offsetMap);
  + outerTr.step(step.map(offsetMap));
  }
  }
  