there doesn’t seem to be any difference between safe and “normal” mode, but indeed on mobile you have to see twice the end of the topic and spend a little time there for it the be marked as read, I’m not sure if it’s intended as one time is enough on desktop.
Yeah I tried testing via safe-mode and it doesn’t seem to make a difference. I am experiencing the same thing on Discourse Meta as well where a read topic is not greyed out (Chrome/iOS). Is it an iOS issue?