Plexamp Desktop Linux Window Focus Issues

Plex Labs
1

I ran some more tests because I’ve developed a strange window/focus problem with the newer Plexamp Flatpaks on Bazzite.

The symptom is that Plexamp starts and stays running, but the window won’t remain visible/focused. If I Alt+Tab to Plexamp, nothing appears. If I then click another application such as Firefox, the Plexamp window briefly flashes on screen and immediately disappears again. Plexamp itself does not crash.

I did a clean reinstall and completely removed ~/.var/app/com.plexamp.Plexamp, so this also occurs with a brand-new Plexamp profile.

I then tested older builds while keeping the rest of the environment unchanged:

  • 4.50.8: works normally; window focuses and remains visible.
  • 4.50.9: problem occurs.
  • 4.50.9-test.bazzite: problem occurs.
  • 4.50.18: problem occurs.

The interesting part is that the exact 4.50.9-test.bazzite build you gave me previously worked correctly when I originally tested it. So the test build itself hasn’t changed, but it no longer works correctly in my current environment.

I also rolled the GNOME 50 runtime back from the current build to older GNOME 50 commits, including:

fc150bcbb560aebb920738976c963cbdb7f83498d583221dadd942870b1bf307

The problem still occurs, so it doesn’t appear to be caused simply by the latest GNOME 50 runtime update.

I also tested forcing Plexamp to X11:

flatpak run --nosocket=wayland --socket=x11 --env=GDK_BACKEND=x11 com.plexamp.Plexamp

KWin confirmed Plexamp was actually running as an X11 window, but the same disappearing-window behavior occurred.

Native Wayland still requires WEBKIT_DISABLE_DMABUF_RENDERER=1 on this NVIDIA system. Without that workaround Plexamp exits with:

Gdk-Message: Error 71 (Protocol error) dispatching to Wayland display.

Current system:

  • Bazzite 44.20260916
  • KDE Plasma / Wayland
  • NVIDIA RTX 4070 Ti
  • NVIDIA driver 615.71.09
  • Plexamp’s Flatpak sandbox is correctly using nvidia-615-71-09

KWin’s debug console sees Plexamp as a normal managed window (normalWindow: true, hidden: false, minimized: false, wantsInput: true), but active remains false when the problem occurs.

There are no custom KWin focus rules, and restarting KWin does not fix it.

The main clue seems to be that 4.50.8 still works in the current environment, while every GNOME-50-based Plexamp build I’ve tested has the problem, including the exact 4.50.9 Bazzite test build that previously worked.

Let me know if there are any WebKitGTK/GTK/Tauri logs, environment information, or debug builds you’d like me to collect. I can reproduce it consistently.

2

Update — I believe I’ve isolated this to WebKitGTK 2.54.0 in the GNOME 50 Flatpak runtime.

I now have a repeatable A/B test using the same Plexamp 4.50.19 beta, same profile, same Bazzite/KDE Wayland session, and same NVIDIA 615.71.09 driver.

Current GNOME 50 runtime contains WebKitGTK 2.54.0 and Plexamp has the window/focus problem.

I rolled org.gnome.Platform//50 back to:

fc150bcbb560aebb920738976c963cbdb7f83498d583221dadd942870b1bf307

dated 2026-09-10.

That runtime contains WebKitGTK 2.52.5. With no change to Plexamp itself:

Plexamp 4.50.19 + GNOME 50 / WebKitGTK 2.54.0 → broken

Plexamp 4.50.19 + GNOME 50 / WebKitGTK 2.52.5 → works normally

I also tested the same Plexamp 4.50.19 against GNOME 48 / WebKitGTK 2.50.6 and it works normally there as well.

This also explains why the 4.50.9-test.bazzite build you gave me originally worked at the time but exhibits the problem now—the Plexamp build didn’t need to change; the GNOME 50 runtime underneath it did.

There’s also an upstream WebKitGTK report with another KDE Wayland/NVIDIA 615.71.09 user reporting a regression between WebKitGTK 2.52.5 and 2.54.0, including the same Wayland Gdk-Message: Error 71 (Protocol error) I’ve encountered.

For now, rolling GNOME 50 back to the Sep. 10 runtime with WebKitGTK 2.52.5 makes current Plexamp 4.50.19 work normally again.