|  | <meta charset="utf-8"> | 
|  | <title>CSS Scrollbars: scrollbar-width on the body is not propagated quirks mode</title> | 
|  | <link rel="author" title="Luke Warlow" href="mailto:luke@warlow.dev" /> | 
|  | <link rel="help" href="https://drafts.csswg.org/css-scrollbars-1/" /> | 
|  | <script src="/resources/testharness.js"></script> | 
|  | <script src="/resources/testharnessreport.js"></script> | 
|  | <script src="/css/support/parsing-testcommon.js"></script> | 
|  | <style> | 
|  | :root { | 
|  | /* CSS scrollbar properties applied to the root element | 
|  | will be propagated to the viewport. */ | 
|  | scrollbar-width: thin; | 
|  | overflow: visible; | 
|  | } | 
|  |  | 
|  | body { | 
|  | /* overflow is propagated as well */ | 
|  | overflow: scroll; | 
|  | /* but CSS scrollbar properties applied to the body are not propagated */ | 
|  | scrollbar-width: none; | 
|  | } | 
|  |  | 
|  | :root, | 
|  | body { | 
|  | margin: 0; | 
|  | padding: 0; | 
|  | } | 
|  |  | 
|  | #content { | 
|  | height: 10vh; | 
|  | width: 100%; | 
|  | background: lightsalmon; | 
|  | } | 
|  |  | 
|  | #expander { | 
|  | /* force vertical scroll */ | 
|  | height: 200vh; | 
|  | width: 300px; | 
|  | background: gray; | 
|  | } | 
|  | </style> | 
|  |  | 
|  | <body> | 
|  |  | 
|  | <div id="content"></div> | 
|  |  | 
|  | <div id="expander"></div> | 
|  |  | 
|  | <script> | 
|  | test(function () { | 
|  | let root = document.documentElement; | 
|  | let body = document.body; | 
|  | let content = document.getElementById('content'); | 
|  |  | 
|  | assert_less_than(root.offsetWidth, window.innerWidth, "viewport has a scrollbar"); | 
|  | assert_equals(body.offsetWidth, root.offsetWidth, "body matches root"); | 
|  | assert_equals(content.offsetWidth, body.offsetWidth, "content matches body"); | 
|  | }, "viewport displays a scrollbar"); | 
|  | </script> | 
|  | </body> |