I enabled nested replies for all topics (Horizon theme) and hit a state bug I can now
reproduce, on both mobile and desktop.
When I open a topic, read it, and then jump to another topic via the suggested/related
topics block (so client-side navigation, no reload), replies from the topic I just left
sometimes stay on screen — rendered nested under the first branch of the new topic.
They even attach under a post that’s been deleted in the new topic. It doesn’t clear if
I keep navigating to more topics; only a full page reload gets rid of it.
One important detail: it’s intermittent. The first hop through the related block is
usually fine, and I can click through it several times with no problem. It only seems to
show up after navigating through the related topics block two or more times in a row.
Steps to reproduce:
- Open a topic with nested replies.
- Open another topic through the suggested/related block (no reload), and keep doing
this a few times in a row. - After two or more consecutive hops through the block, replies from a previous topic
appear nested under the first branch of the current topic, sometimes under a post
that is deleted there. - They persist across further in-app navigation until a hard reload.
There’s no JS error in the console, so I went into the Network tab, and it looks like the
previous topic is simply never torn down:
- The inspected page is topic 724 (/n/vibriruet-pri-troganii…/724?sort=old).
- While I’m on 724, a request for the previous topic’s data is still in the log:
509.json?sort=old&track_visit=true. - The live message-bus poll still has Referer …/n/pinki-tolchki-…-na-nissane-kube/509
— i.e. topic 509’s message-bus subscription was never re-pointed at 724.
So it really seems like the nested route doesn’t reset the post stream / message-bus
subscription of the topic you came from on client-side navigation. First noticed on
mobile, but it behaves the same on desktop.
Discourse version: 2026.6.0-latest (27f76aa897)
Happy to attach a screen recording or dig further if that helps.