It’s not for marking read. It for hiding posts which have been marked as read from the feed without having to refresh the feed, and thus loose your place.

[–] Dazza 2 points 2 years ago (2 children)

Thanks for this explanation. Am I right in that posts are not marked as read unless you click on them and open them?

[–] RustedSwitch 2 points 2 years ago (1 children)

There are a couple of ways to mark a post as read - opening the post is one way, and voting is another. I think viewing a picture in the feed also marks as read.

[–] nocturne213 2 points 2 years ago

Viewing an image, for me at least, is bugged and not making those threads read even when the option is selected in my settings.

[–] th3dogcow 2 points 2 years ago

You can control the settings. Settings ➡️ content ➡️ hide read posts