## What happened

Pressing the bar's Dictation indicator twice within ~0.3 s launches `omarchy-voxtype-config` twice (`Dictation.qml` runs it from `onPressed`). Each run unconditionally calls `omarchy-restart-shell` after spawning the terminal, and `omarchy-restart-shell` has no guard against a concurrent instance. The first restart kills the old shell and launches a replacement; the second restart's `quickshell kill` loop finds that replacement ~270 ms into startup and kills it. Quickshell then segfaults while a plugin's `IpcHandler` registers against the already-destroyed engine generation.

Symbolized stack (Arch debuginfod, quickshell 0.3.1-1):

```
#5 __cxxabiv1::__dynamic_cast (src_type=EngineGenerationExt, dst_type=qs::io::ipc::IpcHandlerRegistry)
#6 qs::io::ipc::IpcHandler::updateRegistration  src/io/ipchandler.cpp:318
#7 qs::io::ipc::IpcHandler::onPostReload        src/io/ipchandler.cpp:278
#8 QQmlObjectCreator::finalize
#9 QQmlComponentPrivate::complete
```

Journal timeline, relative to the first `omarchy-voxtype-config` launch:

| t (s) | event |
|---|---|
| 0.00 | `xdg-terminal-exec ... voxtype configure` launched (first press) |
| 0.33 | same command launched again (second press) |
| 2.11 | old shell: `Exiting due to IPC request` |
| 2.38 | new shell: `Launching config` |
| 2.65 | new shell: `Exiting due to IPC request` |
| 2.78 | `Quickshell has crashed` (SIGSEGV), `crashed within 10 seconds of launching. Not restarting` |
| 3.28 | second restart's launch comes up; the first launcher's retry logs `An instance of this configuration is already running` |

The identical sequence (two `voxtype configure` launches 0.17 s apart, then the same `IpcHandler::updateRegistration` segfault) happened on this machine ten days earlier, so it is reproducible. No OOM, plenty of free memory, no package changes in between.

#8647 shows the same `quickshell +0x16420b` / `+0x167713` offsets as an unexplained SIGSEGV "amid session-restart churn (shell exited twice via IPC requests in the preceding 5 s)"; that is this bug. #7076 describes a second `omarchy-restart-shell` racing the first without a crash.

## Expected

Two presses on the Dictation indicator, or two overlapping `omarchy-restart-shell` calls, should not kill a shell that is still loading.

## Steps to reproduce

1. Have Voxtype installed so the Dictation indicator is in the bar.
2. Double-click the indicator.
3. Watch `journalctl --user -t omarchy-shell -f`: two `Exiting due to IPC request` lines ~0.5 s apart, the second within ~300 ms of `Launching config`, then the SIGSEGV.

## Suggested fixes

- Serialize `omarchy-restart-shell` (e.g. `flock`) so a concurrent call waits instead of killing the sibling's freshly launched shell.
- `omarchy-voxtype-config` should not restart the shell unconditionally, or at least not until the terminal it spawned has exited.
- Debounce `onPressed` in `Dictation.qml`.

The use-after-free itself (registering an `IpcHandler` against a destroyed `EngineGenerationExt` when an IPC kill lands mid-load) is upstream quickshell, but Omarchy's scripts create the condition.

## System

Omarchy 4.0.1-1, quickshell 0.3.1-1, qt6-base 6.11.2-2, qt6-declarative 6.11.2-1, Hyprland.

Filed by Claude Fable 5.1 via Claude Code.