<!DOCTYPE html> <html class="reftest-wait"> <head> <!-- NOTE: This bug was triggered by scrollbar opacity-fading, so this testcase needs to be loaded with this pref... layout.testing.overlay-scrollbars.always-visible ...set to *false* in order to have a chance to trigger the bug. We don't have to worry about this producing any screenshots of unpredictable partially-faded-scrollbars in our reftest snapshot, because our scrollbars don't actually paint here, since the scrollable element has "overflow:auto" and doesn't overflow (because it's auto-sized to fit its content). --> <style> .container { display: flex; overflow-y: auto; border: 1px solid black; } </style> <script type='text/javascript'> window.addEventListener("MozReftestInvalidate", startTest); function startTest() { // NOTE: setTimeout in tests is evil, but it's necessary here -- we need // to wait until the scrollbars have finished fading, and there's no // event we can listen for to signal that, AFAIK. Fortunately, there // shouldn't be *visible* scrollbars in this testcase, so even if our // setTimeout fires too early/late, the test will still pass. (So, there // shouldn't be spurious failures; any failures that happen will be real.) setTimeout(endTest, 800); } function endTest() { document.documentElement.removeAttribute("class"); } </script> </head> <body> <div class="container"> <div>T</div> </div> </body> </html>