static int minXOfFirstNChildren_rightOf(final Container c, final int n, final int minX) {
  ret swing(func -> int {
    int x = c.getWidth();
    for (Component child : takeFirst(n, getChildren(c)))
      if (child.getX() >= minX) x = min(x, child.getX());
    ret x;
  });
}

Began life as a copy of #1020056