No idea what it looks like on mobile but when you scroll down in a topic to the suggested topics it’s hard-ish to see the difference between read and unread ones. The read ones are slightly darker than the unread topics. It might be just me and my blindness but I have a hard time seeing the difference, especially when my screen brightness isn’t on 100%. I’m assuming it’s because of the dark background.
I would provide a picture but I’ve read everything already. Whoops.
Edit: Not just on the suggested topics but on the /latest as well. But suggested is where I pretty much click so that just popped first into my mind.