A user, craigconstantine, reports that category links on their hosted Discourse forum are broken, leading to an error. The issue occurs both for logged-in users and anonymous visitors. After troubleshooting, it’s identified as a conflict with the third-party Topic List Previews Theme Component installed by the user. The problem is linked to an upcoming core change, and the component’s author has since updated it to resolve compatibility. The user decides to switch to alternative components, Topic List Thumbnails and Topic List Excerpts, and the issue is confirmed not to be a Discourse bug. JammyDodger and Lilly assist in diagnosing the problem, with the final fix confirmed by david via GitHub.
Is anyone else on HOSTED DISCOURSE seeing this? …I emailed the team an hour ago, but haven’t heard anything yet.
for example, all the links from my categories page, Categories - Podtalk Community simply lead to this error
error from safari inspector…
repro in Chrome, not logged in as any user…
Ooof. Sorry for the disruption here. Let me see if I can find something out. 
If anyone else is experiencing it please shout out. 
I have a forum on a hosted instance and I am not seeing this error.
I notice it isn’t happening in safe mode on your forum, so it is likely a plugin or component. 
Have you made any changes lately?
I haven’t made changes to components recently.
I did just create a new category… which led to me discovering the problem. So maybe there’s an odd sideeffect to cat creation . . .
I do have two custom components installed (that I wrote)… disabling those didn’t fix the problem. But works-in-safe-mode is a start at troubleshooting.
I bet it’s this
OP’s error (that’s me) was for both logged-in as an admin user, and for anons.
After a little discussion in PM, we think we’ve tracked it to the Topic List Previews (TLP) (cc. @merefield 
)
I have that component installed. Disabling it just resolved the category-links-not-working issue
Discourse team members have rightly pointed out (in pm) that that component is third-party…
I’m going to look into switching to the Topic List Thumbnails and Topic List Excerpts components.
…and I’ve moved this over to Support as it’s not a bug [in Discourse].
Just closing the loop here - @merefield has now made the necessary updates to the Pavilion theme component, so it should work well both before and after the incoming core change 
https://github.com/paviliondev/discourse-tc-topic-list-previews/pull/31
