On my iPhone (7, iOS 13) it’s a bit messy. If these things have already been raised, apologies, I’ve not read the thread.
The header wraps the hamburger onto the following line and obscures a chunk of whatever the menu is that appears underneath it.
Some of the elements are still light with dark text, which is jarring in an otherwise low-key theme.
Swiping up and down while the focus is in the post box is a nightmare: it’s frequently unresponsive when swiping up, and if swiping down the double-sized header appears and leaves a tiny sliver of content between it and the keyboard.
The typography still isn’t very readable to my eye. Some looks like a safe bet for failing basic accessibility criteria by some margin.
A small number of threads appear to have a blue double chevron which seems to take me to a page with no parts on it, which is odd. (Edit: I see what that is now. For some reason the first one I tried gave me no posts to look at, go figure. Presumably related to the fact that the post count and “last updated” link on here have both always been a bit of a lottery on multi-page threads.)
Editing a post takes you to a page that looks empty until you accidentally swipe up and find the edit box was some way below the screen.
And the classifieds link seems to be broken.
One thing I’m glad to see is that images don’t seem to acquire a foggy overlay when you touch them, which used to be a real pain if you were trying to zoom in at all.