Bizarre behaviour with output section

So recently the output area of all exercise pages have been shifting up to the top of the browser. I am using a Mac and working on Safari. It used to work well but only recently started to this!
I have included a photo of it happening. Every time I refresh the page, its starts again (from the normal position and slowly starts to move up)

Works well on Windows.

Any ideas?

This exact same thing is happening to me and I don’t know how to fix it either. Bump.