We’ve built a custom Discourse theme where specific categories are displayed on the homepage using JavaScript. The script uses a predefined list of category names (as a comma-separated array) to fetch and render content from /categories.json. While most categories are displaying correctly, a few are missing from the homepage—even though they are explicitly listed in the script and exist in the system with valid category IDs. Upon inspecting the /categories.json response, we found that these specific categories are not included in the API output at all. However, they: Exist in the Discourse instance Are top-level categories Have everyone set with at least “See” permissions Are not archived, hidden, or nested We’re trying to understand: Under what conditions does Discourse omit categories from categories.json? How can we ensure all needed categories appear in that response, especially if we want to display them on the homepage via custom code? Any insights or recommended solutions would be appreciated.

Not sure, but is this on /latest? Maybe it includes only categories that have topics in the topic list?

this is on latest discourse version and it doesn’t have any topics yet…I tried to create one dummy topic to one of the invisible category based on category ID , presuming it will invoke the categories json to list them but didn’t help & hence deleted the dummy topic as well..currently both categories has any topics…

Sounds like I’m right. It would be silly to have latest send a bunch of categories that are not used on the outage. I think what I would do is either hard code the categories you want or put them in a theme setting. You could also make an Ajax call, but that would slow things down.

FWIW I’ve just created an empty category and I can see it in my /categories.json [The image is a JSON data screenshot showing a structure with categories, topics, and post details, including specific IDs, names, colors, and text values. (Captioned by AI)]

Right. I think if you get that endpoint it’ll have an categories but that the categories included in /latest are probably only those needed for those topics.

I’ve probably got confused. :melting_face: I thought it was about the /categories.json not including certain categories for an unknown reason and thought I’d try and rule out ones with no topics being the cause. Don’t mind me… :slight_smile: [image]

It’s not clear that I’m the one who was confused. And we can both be right. I’m still not clear what it was the the OP was looking at.

Thanks Pfaffman, JammyDodger. Since we’re using a customized theme, we attempted to add a few previously hidden categories to the homepage by appending them to the existing list of exposed categories in our JavaScript. We already have five categories displaying correctly using this method. However, adding these two additional categories does not result in them appearing on the homepage. To troubleshoot, we even tried posting a topic in one of them to see if that would trigger visibility, but it had no effect.

[image] Steve_John: we attempted to add a few previously hidden categories to the homepage by appending them to the existing list of exposed categories in our JavaScript You might share your code, perhaps linking to github

Enabling the lazy load, resolved this issue to display the categories which was not visible earlier..Not sure, how it is related…However it implies that categories doesn’t have any permission issue..still haven’t found the root cause to resolve this issue.

Categories Missing from `categories.json` Despite Existing in the System (Custom Theme)

Development

pfaffman (Jay Pfaffman) May 20, 2025, 12:09am 14

That lazy load code, I think, is designed not to send categories it thinks don’t need to be sent. I’m not sure hour to convince it you want all the categories.

Topic		Replies	Views
Categories.json API not returning Lounge and Staff categories Product Support	5	884	October 12, 2018
category is not returned when searching for categories.json Bug rest-api	6	394	April 19, 2024
Muted categories appear in Categories page UX	16	2634	November 17, 2021
Existing category invisible on page but visible when re-ordering categories Product Support	16	892	April 3, 2023
View of all categories is blocked for anonymous viewers Product Support	13	538	February 14, 2026

Categories Missing from `categories.json` Despite Existing in the System (Custom Theme)

Related topics