Safari displays text after floated element wrong when text has negative top margin

Question

If text after a floated element has negative margin top Safari displays text over the image instead of on its right side. All other browsers display the text on the right side of element. Is this a bug in Safari?

Demo: https://codepen.io/smohadjer/pen/RLBKGb

HTML

<article>
  <h1>Safari's float bug</h1>
  <div class="box">
    container
  </div>
  <p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p>
</article>

CSS

article {
  max-width: 400px;
}

div.box {
  float: left;
  margin: 0 10px 10px 0;
  width: 200px;
  height: 100px;
  background: #ccc;
}

p {
  margin-top: -5px;
}