Photos sidebar not opening

The Basics

  • Nextcloud Server version (e.g., 29.x.x):

    • “33.0.3.2”
  • Operating system and version (e.g., Ubuntu 24.04):

    • Ubuntu 24.04.4
  • Web server and version (e.g, Apache 2.4.25):

    • n/a – AIO
  • Reverse proxy and version _(e.g. nginx 1.27.2)

    • n/a
  • PHP version (e.g, 8.3):

    • n/a AIO
  • Is this the first time you’ve seen this error? (Yes / No):

    • yes
  • When did this problem seem to first start?

    • 2026-05-21
  • Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.

    • AIO
  • Are you using CloudfIare, mod_security, or similar? (Yes / No)

    • Tailscale

Summary of the issue you are facing:

Open photos. Open a photo. Click on 3 dots. Select open sidebar. Nothing happens.

Same problem on Firefox and Chromium.

Edit: I don’t know if something I did changed the situation, or if my first test was too quick. But the sidebar does seem to work on Chromium. It is not opening on Firefox.

Check browser inspector as described in the body of the support template.

Found this bug report on GitHub: Nextcloud Photos issue #3426

Also, I can reproduce this issue on all my instances. These include regular Apache/LAMP setups both with and without Caddy in front of them, as well as one AIO instance. So I think I can pretty much rule out configuration issues on my side, which makes this most likely a bug in Nextcloud itself and/or the Photos app.

Sometimes the sidebar works. Then it doesn’t. At the moment it’s not working in Chromium nor in Firefox.

The messages I see in the browser vary, but this one seems relevant:

Refused to apply style from ‘https:///apps/files_versions/css/sidebar-tab.css?v=660cac32-0’ because its MIME type (‘text/html’) is not a supported stylesheet MIME type, and strict MIME checking is enabled.

What seems to help is to log out and then back in.