<!doctype html>
<title>CSS Overflow Reference: scrollbar-gutter is accounted for in abspos sizing</title>
<style>
.container {
  scrollbar-gutter: stable;
  overflow-y: auto;
  width: 100px;
  height: 200px;
  position: relative;
}
.child {
  width: 100%;
  height: 100px;
  background: green;
}
</style>
<div class="container">
  <div class="child"></div>
</div>
