chromium/third_party/blink/web_tests/fast/borders/border-shadow-large-radius.html

<!doctype html>
<html>
<head>
<style>
div {
  width: 500px;
  height: 200px;
  margin: 30px 30px 20px 30px;
  background: blue;
  padding: 0px;
}
    
.neg-shadow {
  box-shadow: 260px 30px 0px -10px lime;
}
    
.rounded1 {
 /* 191px triggers the square shadow 190px doesn't  |  200px triggers the missing section of shadow and a square shadow;  199px doesn't but keeps the square  */
  border-radius: 0 0 200px 0;
}
</style>
</head>
<body>
<!--[bug 72103] Test box-shadow with negative spread. Even if the spread is negative, the shadow's shape should not be a rectangle. The box shadow should be rounded.-->
<div class="neg-shadow rounded1"></div>
</body>
</html>