re: For those on Desktop, click "Go to Beta" link at top of page to test out new version

Cap crunch, what device are you using? Assuming you are in desktop, when inside a post, you should click the "Back to top" link found inside each post. If on the index, you don't have to go far to get to top.

Making the bar stick to top presents some design issues/decisions we don't want to tackle yet.