## What happened

Screensaver / idle lock fires on schedule (`idle.screensaver` in
`~/.config/omarchy/shell.json`) even while a video is actively playing in
Firefox (e.g. YouTube). The video keeps playing behind the screensaver —
Firefox never successfully inhibits idle.

## What I expected

Playing video in the browser should suppress the screensaver/lock the same
way it does on GNOME/KDE, for the duration of playback.

## Root cause (traced via journal + source)

Omarchy's idle system is a Quickshell service
(`/usr/share/omarchy/shell/plugins/services/idle/Service.qml`), not
`hypridle` — no `hypridle` process runs in an Omarchy session even though
`~/.config/hypr/hypridle.conf` still ships/exists. The Quickshell service
uses `Quickshell.Wayland.IdleMonitor` with `respectInhibitors: true`, which
only honors **Wayland-protocol** idle inhibitors
(`idle-inhibit-unstable-v1`), the kind fullscreen `mpv`/VLC register
directly against a surface.

Firefox instead requests idle inhibition via the **freedesktop portal**
(`org.freedesktop.impl.portal.Inhibit`) while a `<video>` is playing. Tracing
that call:

- `/usr/share/xdg-desktop-portal/portals/hyprland.portal` (the backend
  selected `UseIn=... Hyprland ...`) does **not** list
  `org.freedesktop.impl.portal.Inhibit` in its `Interfaces=` — only
  `Screenshot;ScreenCast;GlobalShortcuts;InputCapture`.
- `xdg-desktop-portal` therefore falls back to
  `xdg-desktop-portal-gtk` (`UseIn=gnome`) as the only backend implementing
  `Inhibit`.
- `xdg-desktop-portal-gtk`'s Inhibit implementation proxies to the legacy
  `org.freedesktop.ScreenSaver` D-Bus interface — but nothing in an Omarchy
  session owns that well-known name (no gnome-screensaver-alike service), so
  every call fails.

Journal, repeating every few seconds while the video plays:

```
xdg-desktop-portal-gtk[1929]: Backend call failed: Cannot invoke method; proxy is for the
well-known name org.freedesktop.ScreenSaver without an owner, and proxy was constructed
with the G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START flag
/usr/lib/xdg-desktop-portal[1739]: A backend call failed: Inhibiting other than idle not supported
```

So the inhibit request is silently swallowed and the Quickshell idle monitor
never sees it — the screensaver/lock timers proceed unaffected by playback.

Notably, Omarchy's idle service already has the exact mechanism needed to
fix this cleanly: the existing `stayAwake` state
(`~/.local/state/omarchy/indicators/stay-awake`, toggled via the bar's "Stay
Awake" indicator or `omarchy-shell idle enable|disable`). A small D-Bus
service that implements `org.freedesktop.ScreenSaver`
(`Inhibit`/`UnInhibit`) — or extending `xdg-desktop-portal-hyprland`'s
`.portal` file / omarchy-shell to implement
`org.freedesktop.impl.portal.Inhibit` — and drives that same `stayAwake`
flag would let Firefox (and any other portal/D-Bus-based app: mpv without
`--no-osc`... etc.) properly suppress idle during playback.

## Steps to reproduce

1. Fresh Omarchy session on Hyprland (not GNOME).
2. Open Firefox, play any YouTube video (windowed, not fullscreen).
3. Leave mouse/keyboard untouched past `idle.screensaver` seconds
   (default/configured 300s here).
4. Screensaver launches while video audio/playback continues in the
   background.
5. `journalctl --user -b | grep -i -E 'ScreenSaver|Inhibit'` shows the
   failed D-Bus calls timed to the video's inhibit heartbeat.

## System details

- Omarchy: 4.0.0-1
- Hyprland: 0.56.2-1
- xdg-desktop-portal: 1.22.1-2
- xdg-desktop-portal-gtk: 1.15.3-1
- xdg-desktop-portal-hyprland: 1.4.1-1
- Firefox: 153.0.4-1
- Kernel: 7.1.8-arch1-3
- GPU: AMD Radeon RX 7900 XTX (amdgpu), iGPU Raphael
- `idle.screensaver` = 300s, `idle.lock` = 604800s (per `~/.config/omarchy/shell.json`)

## Workaround

Toggle the bar's "Stay Awake" indicator (or `omarchy-shell idle disable`)
before watching video, and `omarchy-shell idle enable` afterward.