Users report a persistent bug where unread post counts appear for topics that are not being tracked, even after previously visiting them. schneeland first observed this when opening topics in new tabs or navigating quickly on mobile, and notes it now also occurs on desktop—even for topics never visited before. Screenshots illustrate the issue, including an unread indicator appearing despite the topic not being tracked. NateDhaliwal confirms the bug has existed for years and notes that reloading the page temporarily removes the indicator. Jagster agrees it’s long-standing, attributing it variably to Apple, DiscourseHub, or internal Discourse timers/caching. schneeland adds that while previously only noticed on mobile during rapid navigation, the issue now also affects desktop and even unvisited topics, suggesting a possible regression or expanded scope. The behavior mirrors an old bug believed to be fixed, indicating this may be a re-emergence or related issue.
I have observed that sometimes, when I open a topic that I have visited previously, but which has new posts, I get an an unread count, even if I am not tracking the topic - today, this happened when I opened the topic in a new tab, but I have also seen this if I visit a topic on mobile but navigate back quickly.
The behaviour seems like what is described in this old bug, which is supposedly fixed.
Example screenshots:
Main page after opening two links in the background:
True. I have to say, I only noticed it on mobile and online when navigating back and forth quickly, before. Having it appear on Desktop is a new thing for me.
Also, I just had it happen even for a topic that I did not visit before: