Mobile tweak suggestion:
If a post has already been highlighted or postmarked, remove the ability to tap on the ribbon and have the "Do you want to postmark this post?" dialog pop up. The ribbon icon and the forward/backward arrows are very close together, and it's easy to accidentally tap the ribbon when trying to navigate to the next highlight, which then triggers the postmark request prompt. If a post is already highlighted, the request postmark function should be disabled, if possible, so nothing happens if the highlight ribbon is tapped.