List of steps to reproduce (step by step, including full links if applicable):

• Scroll to the top of the page.
• Note where the text is cut off at the bottom, by the edge of the viewport.
• Hit the 'page down' key.
• Wait a moment for the the sticky header to appear.
• Note where the text is cut off at the top, by the sticky header.

What happens?:

• The sticky header obscures the overlapping text and effectively scrolls too far, going past some text that was not visible before scrolling.

What should have happened instead?:

• There would be some overlap between the text visible at the bottom before scrolling and the text visible after scrolling, so that you don't need to manually scroll up with arrow keys to re-find your place.