<!DOCTYPE html> <html lang="en" class="reftest-wait"> <meta charset="utf-8"> <title>Changes to background-position should invalidate properly for fieldsets.</title> <style> body { margin: 0; } #background { width: 100px; height: 100px; background-image: url(image_rgrg-256x256.png); background-repeat: no-repeat; background-position: 0 0; border: 0; padding: 0; margin: 0; } </style> <fieldset id="background"><legend></legend></fieldset> <script> function doTest() { document.querySelector("#background").style.backgroundPosition = "-140px 0"; document.documentElement.removeAttribute("class"); } document.addEventListener("MozReftestInvalidate", doTest); </script>