<!DOCTYPE html>
<!--
 | Empty inline-block should be treated as if it was non-empty text.
 -->
<html>
<head>
  <style>
    body {
      margin: 0px;
      font-family: Roboto;
      font-size: 100px;
      font-weight: bold;
    }
    .inline-block {
      display: inline-block;
    }
    .not-collapsed {
      background-color: #4caf50;
    }
  </style>
</head>
<body>
  <div><div class="inline-block"></div><span class="not-collapsed"> </span>Hello, world!</div>
  <div>Hello,<div class="inline-block"></div><span class="not-collapsed"> </span>world!</div>
  <div>Hello, world!<span class="not-collapsed"> </span><div class="inline-block"></div></div>
</body>
</html>