int getLookupStart(@Nullable Throwable disposeTrace) {
    if (!myLookupStartMarker.isValid()) {
      throw new AssertionError(
        "Invalid lookup start: " + myLookupStartMarker + ", " + myEditor +
        ", disposeTrace=" + (disposeTrace == null ? null : ExceptionUtil.getThrowableText(disposeTrace)) +
        "\n================\n start dispose trace=" + (myStartMarkerDisposeInfo == null ? null : myStartMarkerDisposeInfo.get()));
    }
    return myLookupStartMarker.getStartOffset();
  }
int getLookupStart(@Nullable Throwable disposeTrace)