There are no visible cues hinting at ability to navigate from one expanded post to the next (or previous).
Navigating back to the post list (using back button), and then to next post makes it slow, and click heavy.
Keyboard shortcuts work, but there are again no visible cues indicating even their presence.
No visible hints that any keyboard shortcuts exist
Keyboard shortcut discoverability is solely by trial and error, or ‘Google’
Traditionally, pressing ‘?’ (in, say, GMail or Pocket) brings up relevant shortcuts modal. Doesn’t work in reader.
One suggested hint could be to place a keyboard icon next to the help (?) icon, at the bottom, in the left navigation bar.
j/k navigate to next/previous post as expected. However, the more ‘lay’ user-friendly left-arrow/right-arrow versions don’t.
esc key works the same as browser’s back button – navigating back through history stack (i.e. going back to last viewed post).
A better (expected) implementation would be to jump out of expanded-post view to the posts list view, ideally scrolled to the last viewed post.
Like keyboard shortcut, l, works as expected. Adding f as an additional activator would be useful – a lot of platforms use favourite as an alternative to like, and some users may be more behaviourally trained to press f instead of l