See the latest beta for a new, general-purpose nav slug.
And here’s an example of how it might be used to recreate the new navigation layout in presentation mode.
<div class="top-divider-links">
<a href="=$nav-next-link$=" class="nav-link">
↓
</a>
<a href="=$nav-prior-link$=" class="nav-link">
↑
</a>
<a href="=$nav-top-link$=" class="nav-link">
⌂
</a>
</div>