Video black screen + app freezes on subsequent launches

[Darogirn]

I wanted HDR on my linux desktop. On V4 not possible except with external player. So I wanted to try the AUR package stremio-linux-shell-git, but it has packaging issues (missing CEF files)
stremio-enhanced-bin (Electron/web version) fails with "video is unsupported" (I think HDR wouldn't have worked anyway with Stremio-web)
That's why I then wanted to try the Flatpak version. On Wayland with NVIDIA, the Flatpak version has two issues:

Video playback shows black screen on first launch
App becomes unresponsive on subsequent launches

System Information

OS: CachyOS 
Desktop: Hyprland 
GPU: NVIDIA RTX 4080 Super
Driver: 580.105.08 

Installation

Installed via:
flatpak remote-add --if-not-exists flathub-beta https://flathub.org/beta-repo/flathub-beta.flatpakrepo
flatpak install flathub-beta com.stremio.Stremio

First launch: UI loads, can browse content, but video playback shows black screen.

Terminal output:

2025-12-12T17:17:58.657505Z ERROR stremio_linux_shell::player: Failed to set property sub-ass-override: Unsupported
Mpv error: Raw(-16)
[176:176:1212/181927.670306:ERROR:services/on_device_model/ml/gpu_blocklist.cc:120] Unable to get gpu adapter
[3:26:1212/181927.670409:ERROR:services/on_device_model/public/cpp/service_client.cc:36] Unexpected on_device_model service disconnect: The device's GPU is not supported.

Also many Error: stream ended from server.js and GCM registration errors.

Second launch onwards: Black screen immediately, app becomes completely unresponsive. Hyprland shows "application not responding" dialog - waiting doesn't help, so I have to terminate:

(node:5) [DEP0005] DeprecationWarning: Buffer() is deprecated...
/app/bin/stremio: line 2: 3 Killed /app/share/stremio/stremio "$@"

Workarounds Attempted

GDK_BACKEND=x11 flatpak run com.stremio.Stremio - same behavior
LIBGL_ALWAYS_SOFTWARE=1 flatpak run com.stremio.Stremio - same behavior

Stremio v4 (Qt-based stremio AUR package) works fine on the same system
HDR works correctly in standalone mpv

I'm looking for native HDR support. The v4 external player workflow lacks autoplay and watch progress tracking, making it impractical.

[perpetus]

To fix the aur version change PKGBUILD like this

package() {
  cd "stremio-linux-shell"

  # Install binary
  install -Dm755 "target/release/stremio-linux-shell" "$pkgdir/usr/bin/stremio"

  # Desktop + icons
  install -Dm644 "data/com.stremio.Stremio.desktop" \
    "$pkgdir/usr/share/applications/com.stremio.Stremio.desktop"
  sed -i '/^[[:space:]]*DBusActivatable[[:space:]]*=[[:space:]]*true[[:space:]]*$/d' \
    "$pkgdir/usr/share/applications/com.stremio.Stremio.desktop"

  install -Dm644 "data/icons/com.stremio.Stremio.svg" \
    "$pkgdir/usr/share/icons/hicolor/scalable/apps/com.stremio.Stremio.svg"
  install -Dm644 "data/com.stremio.Stremio.metainfo.xml" \
    "$pkgdir/usr/share/metainfo/com.stremio.Stremio.metainfo.xml"

  # Install licenses
  install -Dm644 /usr/share/licenses/spdx/GPL-3.0-only.txt \
    "$pkgdir/usr/share/licenses/$pkgname/LICENSE.txt"

  ### ---- CEF runtime bundle ----

  # install CEF libraries into private runtime folder
  install -dm755 "$pkgdir/usr/lib/stremio/cef"
  cp -r vendor/cef/* "$pkgdir/usr/lib/stremio/cef/"

  # Move real binary
  install -dm755 "$pkgdir/usr/lib/stremio"
  mv "$pkgdir/usr/bin/stremio" "$pkgdir/usr/lib/stremio/stremio-bin"

  # Install server.js next to the binary
  install -Dm644 "data/server.js" "$pkgdir/usr/lib/stremio/server.js"

   # Launcher wrapper to load private CEF
  cat > "$pkgdir/usr/bin/stremio" <<'EOF'
#!/bin/bash
export LD_LIBRARY_PATH="/usr/lib/stremio/cef:$LD_LIBRARY_PATH"
export CEF_FLAGS="--enable-features=ClipboardContentSetting --enable-clipboard --disable-gpu-sandbox"
cd /usr/lib/stremio
exec /usr/lib/stremio/stremio-bin $CEF_FLAGS "$@"
EOF
  chmod +x "$pkgdir/usr/bin/stremio"

}

[Darogirn]

Thanks for the fix! The CEF packaging issue is solved.

Unfortunately I still hit the same issue as with the Flatpak: black screen on launch, app is unresponsive, Hyprland shows "not responding" dialog and I have to terminate.

So the packaging is fixed, but there seems to be a deeper compatibility issue with Hyprland/NVIDIA Wayland.

[perpetus]

works fine for me on Wayland KDE plasma using nvidia gpu , might be Hyprland specific issue.

[Darogirn]

After more debugging, I found the actual launch issue was Ozone-related. The app needs explicit Ozone flags:

stremio --enable-features=UseOzonePlatform --ozone-platform=wayland

On KDE Plasma this probably works out of the box.

One more question: does HDR video playback work for you? On my system, HDR works fine in standalone mpv, but Stremio's embedded player doesn't trigger HDR mode.

[perpetus]

Unfortunately i don't have a monitor that supports HDR for testing. I don't think HDR is supported yet in current implementation. MPV can play HDR but i think i gets converted into SDR so the colors will look correct, but your monitor won't switch to "HDR Mode" and you won't get the extra brightness/contrast.

[Darogirn]

Makes sense, thanks for confirming. Would be great to have native HDR support in the future