css/css-overflow/scrollbar-gutter-root-ref.html

<!doctype html>
<meta charset="utf-8">
<title>CSS Overflow: scrollbar-gutter on the root element</title>
<link rel="help" href="https://drafts.csswg.org/css-overflow-4/#scrollbar-gutter-property">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1874093">

<style>
    html {
        background-color: blue;
        margin: 10px;
        padding: 10px;
        border: 5px solid black;
    }

    body {
        margin: 10px;
        padding: 10px;
        border: 5px solid green;
    }

    #abspos {
        position:absolute;
        top:150px;
        left: 0px;
        background-color: green;
        width: 80px;
        height: 100px;
        transform: translateZ(0);
    }

    p {
        background-color: purple;
        color: white;
    }
</style>
<div id="outer" style="width: 100px; height: 100px; overflow: scroll; left: -200px; position: absolute;">
    <div id="inner" style="width: 100%; height: 200%;"></div>
</div>
<script>
    var outer = document.getElementById("outer");
    var inner = document.getElementById("inner");
    // Compute scrollbar gutter size and add it as margin to the root element
    document.documentElement.style.marginRight = String((outer.offsetWidth - inner.offsetWidth) + 10) + "px";
</script>

<p id="content">Should not have space around me in the inline axis.</p>
<div id="abspos"> </div>