Tables and boxes establishing formatting contexts should be positioned next to floats

[liZe]

In CSS 2.1:

The border box of a table, a block-level replaced element, or an element in the normal flow that establishes a new block formatting context (such as an element with 'overflow' other than 'visible') must not overlap the margin box of any floats in the same block formatting context as the element itself.

They currently overlap:

<style>
  div {
    float: right;
    background: #f004;
    width: 50%;
    height: 10em;
    margin: 1em;
  }
  h1 {
    border: 1px solid black;
    overflow: hidden;
  }
</style>
<div>float</div>
<h1>title</h1>