I have an image slider fixed to the top of the site, with every other section set up to go "over" it, so as to have a parallax effect. I had some issues with this before, which I believed I had fixed; However, on Firefox most of the site is not visible.
On Safari, once I reach the bottom of the page, the footer keeps sliding up and the bottom of the slider shows up, as seen in the screenshot bellow.
On Chrome everything works ok.
System and Browser
I am on a 2014 retina MacBook, and used Safari while building the site.
On Safari (Notice the slider peeking out at the bottom. Only when visitng the site, as it works fine within the editor)
On Chrome (Desired appearance)