# Built-in theme preview images missing (404) in discourse/discourse Docker image

**URL:** https://meta.discourse.org/t/built-in-theme-preview-images-missing-404-in-discourse-discourse-docker-image/391859
**Category:** Self-hosting
**Tags:** unsupported-install
**Created:** [21 בדצמבר,‏ 2025,‏ 8:10pm UTC](https://meta.discourse.org/t/built-in-theme-preview-images-missing-404-in-discourse-discourse-docker-image/391859 "2025-12-21T20:10:15Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![YuriEarth](https://avatars.discourse-cdn.com/v4/letter/y/b9bd4f/32.png) [@YuriEarth](https://meta.discourse.org/u/YuriEarth)
#### Post date: [21 בדצמבר,‏ 2025,‏ 8:10pm UTC](https://meta.discourse.org/t/built-in-theme-preview-images-missing-404-in-discourse-discourse-docker-image/391859/1 "2025-12-21T20:10:15Z")

</div>

I’m running Discourse using the experimental `discourse/discourse:3.5.1` Docker image (via Docker Compose, not the launcher) and noticed that the built-in theme preview images are returning 404 errors in the admin themes page.

**Environment:**

- Image: `discourse/discourse:3.5.1`

- Deployment: Docker Compose on Dokploy

- Database: PostgreSQL 17 with pgvector

- Fresh installation (December 2024)

**Issue:** When accessing `/admin/customize/themes`, the browser console shows 404 errors for theme preview images:

```plaintext
https://forum.example.com/uploads/default/original/1X/d7dc093939924a0ce97287d65ec38bbcb2b23e00.png
https://forum.example.com/uploads/default/original/1X/f8a61b9a0bfac672daec9e401787812f8c5e28df.png

```

**What I’ve tried:**

- Created proper upload directory structure: `/shared/uploads/default/{original,optimized}/{1X,2X,3X}`

- Set correct permissions: `discourse:www-data` ownership

- Ran `rake uploads:regenerate_missing_optimized` (completed successfully but didn’t generate these files)

- Ran `rake themes:update` (no effect)

- Verified symlink exists: `/var/www/discourse/public/uploads` → `/shared/uploads`

**Observations:**

- Theme previews work when clicked (themes function normally)

- Only the thumbnail images in the theme selector are missing

- The referenced PNG files don’t exist anywhere in the container

- Database has upload records pointing to these non-existent files

**Question:** Is this expected behavior for the experimental image? Should these preview images be seeded during initialization, or is there a migration/task I’m missing?

The forum works perfectly otherwise - this is purely cosmetic. Just want to confirm if this is a known limitation of the experimental image or if I’ve missed a setup step.

---

<div class="post-metadata">

### Author: ![pfaffman](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/pfaffman/32/120154_2.png) [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [21 בדצמבר,‏ 2025,‏ 9:33pm UTC](https://meta.discourse.org/t/built-in-theme-preview-images-missing-404-in-discourse-discourse-docker-image/391859/2 "2025-12-21T21:33:25Z")

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> [@YuriEarth](#):
>
> Created proper upload directory structure:

You shouldn’t need to do that.

Do uploads work?

Did you run the rake assets:precompile? (or maybe those new images do that automatically–when I started trying to create such images, I think I had them do it on first boot.