Due to feedback on the jerky motion of scrolling from the bottom of a page to the top a smooth scroll was introduced; you could disable this by editing /forums/ubb_js/ubb_jslib.js and changing the 150 to a 0.
Code
// Scroll to the top of the document on click (without changing the url)
function topFunction() {
if (document.body.scrollTop !== 0 || document.documentElement.scrollTop !== 0) {
window.scrollBy(0, -150);
requestAnimationFrame(topFunction);
}
}
