KDE/Plasma Media Player controls only partly work with Jellyfin in the browser

[denilsonsa]

KDE/Plasma has a "Media Player" widget that allows controlling (from one single place) whatever application is playing audio or video. Unfortunately, the back/forward buttons do not work with Jellyfin.

How to reproduce

1. Use KDE/Plasma.
2. Make sure your browser has the Plasma Integration extension.
3. Either:
   • Under System Tray Settings → Entries, make sure Media Player is shown.
   • Or right-click on the desktop → Add Widgets → Media Player → drag it to the desktop. Then right-click → Enter Edit mode → resize the widget to be large enough.
4. Open Jellyfin on the browser.
5. Start playing music.

What happens

The media player correctly shows the cover art, the title, the progress bar. The "Play/Pause" button works. However, both the "Next" and the "Previous" buttons are disabled and don't work.

Untested: the "Shuffle" and the "Repeat" buttons, but I vaguely remember trying them and not working correctly.

Unfortunately, similar to Jellyfin, the Bandcamp website also doesn't work well with Plasma Integration.

Expected Behavior

All buttons should work fine. I should be able to skip (or go back) a song easily through the widget, as it is a significantly better UX than having to find the open Jellyfin tab in the middle of dozens of browser tabs.

In fact, the SoundCloud website seems to work well. I can go to a playlist, hit play, and the KDE/Plasma media player buttons work fine. (Except shuffle/repeat.)

System

• Platform: Manjaro Linux, x86_64, Running KDE/Plasma 5.27.10 on X11
• Browser: Firefox 122, with Plasma Integration browser extension
  • Untested: Google Chrome with Plasma Integration browser extension
  • If anyone is interested in the extension source-code: https://invent.kde.org/plasma/plasma-browser-integration/-/blob/master/extension/content-script.js
• Jellyfin Version: 10.8.13 running on Synology NAS (arm)

[jellyfin-bot]

This issue has gone 120 days without comment. To avoid abandoned issues, it will be closed in 21 days if there are no new comments.

If you're the original submitter of this issue, please comment confirming if this issue still affects you in the latest release or master branch, or close the issue if it has been fixed. If you're another user also affected by this bug, please comment confirming so. Either action will remove the stale label.

This bot exists to prevent issues from becoming stale and forgotten. Jellyfin is always moving forward, and bugs are often fixed as side effects of other changes. We therefore ask that bug report authors remain vigilant about their issues to ensure they are closed if fixed, or re-confirmed - perhaps with fresh logs or reproduction examples - regularly. If you have any questions you can reach us on Matrix or Social Media.

[denilsonsa]

Tested again on my system:

• Manjaro Linux, x86_64, KDE/Plasma 6.0.5
• Browser: Firefox 127.0
• Jellyfin version 10.8.13

You may be able to reproduce on your own system, even if it's a different OS or browser. I cannot test on other systems, though.

---

I managed to reproduce this issue, but it's tricky, as my initial steps weren't accurate enough.

1. Open Jellyfin on the browser. If it was already open, please refresh the page.
2. Without navigating anywhere, play any music album.
   • If you opened Jellyfin on the homepage, play any album from the homepage.
   • You can also click on Favorites, as somehow it's a different tab still on the homepage. Then play any album from your favorites.
   • How to play? Press the ▶PLAY button at the middle of the album artwork. Alternatively, you can also choose Shuffle from the ⋮ menu.
3. Observe how the buttons are working correctly.
4. Still without navigating, play another album.
5. Observe how the buttons are still working correctly. You can use the seek bar, and the previous/next buttons. Even shuffle/repeat seems to be working, although the Jellyfin UI doesn't update the state (and my testing was very limited).
6. Now, navigate Jellyfin. You can go to Music. Or click on any album, or on any artist.
7. Observe how the album art and the song title (on the widget) are now placeholders.
   • The bug has been triggered.
   • From now on, the media controls are broken.
   • Sometimes the play/pause still works, but the next/previous don't work anymore.
   • Sometimes the progress bar (on the widget) continues going, even though there is no music playing on Jellyfin.
   • Sometimes the album art and the song title are restored. Usually after navigating, stopping the playback, and then starting a new playback.

This bug also happens if you navigate first (e.g. to search for a song) and start playing after navigation. In this case, the player starts in this "broken" state.

---

I believe the root cause of this issue is related to:

• Navigating the website triggers a change in the URL. (e.g. from #!/home.html to anything else.)
• Changing the URL causes the routing system to re-render a lot of the page.
• Which causes some re-rendering of the media player, or possibly re-announcing the media player.

This is just a guess, though.

---

I also tested Bandcamp again, and the next/previous buttons still don't work on that website.