Scroll Horizontally, keep story line when accessing through anchor.

### Description

I believe this is a request for a new feature, or an enhancement, rather than a bug.

If a user skips ahead to a section via an anchor link, and then scrolls back UP to a previous section, I would like to be able to transition directly to the last slide of the section rather than the first.

### Link to isolated reproduction with no external CSS / JS

Here is an example built specifically to demonstrate: ***

### Steps to follow on the example url:
1. After page loads, click **Section C** in the top navigation bar
2. After **Section C, Slide 1** has loaded, scroll up to go to **Section B**
3. **B.1** will appear, because the user has never viewed Section B before so it makes sense that B.1 would be the active slide. However, since **B.3** is in some sense the preceding slide to **C.1**, I would like the scrolling action to reveal **B.3**.

Does that make sense? Let me know what else I can do to explain. Thank you.