## Summary

On a ThinkPad, turning Bluetooth **off** from the Bluetooth bar widget makes the
widget disappear, and neither clicking where it used to be nor the
`SUPER+CTRL+B` / IPC toggle can turn Bluetooth back on. Only the physical
`Fn` radio button recovers it.

The cause is that `omarchy-bluetooth-power off` runs `rfkill block bluetooth`,
which also blocks the `thinkpad_acpi` master radio switch. On this hardware that
switch gates power to the internal USB Bluetooth module, so the module
de-enumerates and BlueZ unregisters the adapter entirely. `Panel.qml` then
treats "no adapter" as "no hardware": it hides the widget and makes its toggle a
no-op.

## Environment

- Omarchy: `4.0.4-1`
- Machine: Lenovo ThinkPad T480 (`20L50000MX`)
- Bluetooth module: `Bus 001 Device 051: ID 8087:0a2b Intel Corp. Bluetooth wireless interface`, enumerated at USB port `1-7`

```
$ rfkill list          # after turning Bluetooth off from the widget
0: tpacpi_bluetooth_sw: Bluetooth
	Soft blocked: yes
	Hard blocked: no
1: phy0: Wireless LAN
	Soft blocked: no
	Hard blocked: no
```

## Root cause

`omarchy-bluetooth-power` implements off as:

```bash
rfkill block bluetooth
```

Blocking the `bluetooth` rfkill **type** blocks every switch of that type, and
this ThinkPad exposes two:

1. `platform-thinkpad_acpi:bluetooth` (`tpacpi_bluetooth_sw`) — the master
   switch, which also controls power to the module.
2. The internal USB module itself (`pci-…-usb-0:7:1.0:bluetooth`, USB port `1-7`).

Blocking the `thinkpad_acpi` switch drops power to the USB module:

```
$ ls /sys/bus/usb/devices/      # while Bluetooth is on
… 1-7 1-7:1.0 1-7:1.1 …

$ ls /sys/bus/usb/devices/      # after `rfkill block bluetooth` settles
… (no 1-7) …

$ ls -A /sys/class/bluetooth/   # empty
$ bluetoothctl list             # empty
```

BlueZ therefore unregisters the adapter, and `Bluetooth.defaultAdapter` becomes
`null` in the QML.

`$OMARCHY_PATH/shell/plugins/panels/bluetooth/Panel.qml` then hits two
adapter-null assumptions:

- **Line 500** — `visible: adapter !== null` removes the bar widget entirely,
  and its `icon` (line 59, `if (!adapter) return ""`) would render a zero-width
  button anyway.
- **Lines 636-637** — the toggle bails out:

  ```js
  function toggleBluetooth() {
    if (!adapter) return
    Quickshell.execDetached(["omarchy-bluetooth-power", adapter.enabled ? "off" : "on"])
  }
  ```

  so the panel's switch (line 715, `visible: !!root.adapter`), the right-click
  action, and the `omarchy.bluetooth` IPC handler all do nothing.

`rfkill unblock bluetooth` is exactly what brings the adapter back, and the
patched branch below can issue it while the adapter is absent.

## Steps to reproduce

1. On a ThinkPad (or any machine whose Bluetooth radio sits behind a second
   `rfkill` switch of type `bluetooth`), click the Bluetooth bar widget and turn
   it off (or run `omarchy-bluetooth-power off`).
2. Wait a few seconds for the internal module to power down.
3. The Bluetooth widget vanishes from the bar and `/sys/class/bluetooth/` is empty.
4. Try `SUPER+CTRL+B` → toggle, or `omarchy-shell omarchy.bluetooth toggleBluetooth`:
   nothing happens, the adapter stays gone.
5. Only the physical `Fn` radio button (which flips `tpacpi_bluetooth_sw` back to
   `soft=0` and re-powers the module) restores Bluetooth.

## Suggested fix

Treat "no adapter" as "Bluetooth is off" rather than "no hardware", so the
widget stays reachable and its toggle can re-enable the radio. Diff against
`shell/plugins/panels/bluetooth/Panel.qml`:

```diff
--- a/shell/plugins/panels/bluetooth/Panel.qml
+++ b/shell/plugins/panels/bluetooth/Panel.qml
@@ -56,7 +56,7 @@
   readonly property var discoveredDevices: deviceGroups.discovered || []
 
   readonly property string icon: {
-    if (!adapter) return ""
+    if (!adapter) return "󰂲"
     if (!adapter.enabled) return "󰂲"
     if (connectedDevices.length > 0) return "󰂱"
     return "󰂯"
@@ -75,7 +75,7 @@
   ]
   readonly property bool rotatingPhrases: adapter && adapter.enabled
   readonly property string heroStatusText: {
-    if (!adapter) return "No adapter"
+    if (!adapter) return "Turned Off"
     if (!adapter.enabled) return "Turned Off"
     return activePhrases[phraseIndex % activePhrases.length]
   }
@@ -497,7 +497,7 @@
     if (selectedIndex < 0) selectedIndex = 0
   }
 
-  visible: adapter !== null
+  visible: true
   implicitWidth: button.implicitWidth
   implicitHeight: button.implicitHeight
 
@@ -633,8 +633,10 @@
   // switch only moves once BlueZ catches up, so a second click inside that window
   // would re-read the old state and undo the first.
   function toggleBluetooth() {
-    if (!adapter) return
-    Quickshell.execDetached(["omarchy-bluetooth-power", adapter.enabled ? "off" : "on"])
+    if (adapter)
+      Quickshell.execDetached(["omarchy-bluetooth-power", adapter.enabled ? "off" : "on"])
+    else
+      Quickshell.execDetached(["omarchy-bluetooth-power", "on"])
   }
 
   IpcHandler {
@@ -712,7 +714,7 @@
           // header's only cursor target.
           ToggleSwitch {
             id: powerSwitch
-            visible: !!root.adapter
+            visible: true
             checked: !!root.adapter && root.adapter.enabled
             hasCursor: root.headerHasCursor
             foreground: root.bar.foreground
@@ -867,7 +869,7 @@
         Text {
           textFormat: Text.PlainText
           visible: root.connectedDevices.length === 0 && root.scrollRows.length === 0
-          text: !root.adapter ? "No Bluetooth adapter"
+          text: !root.adapter ? "Bluetooth is off"
               : !root.adapter.enabled ? "Turn Bluetooth on to scan"
               : "Scanning for devices…"
           color: Qt.darker(root.bar.foreground, 1.5)
```

With this applied, the widget stays in the bar showing the off glyph, and
toggling it while the adapter is absent runs `omarchy-bluetooth-power on`
(`rfkill unblock bluetooth`), which powers the module back up and restores the
adapter. All other adapter-null guards in the panel (discovery retry, the
`Connections` targets, `onOpenedChanged`, device sections) already tolerate a
null adapter and need no change.

Tradeoff: on a machine with no Bluetooth hardware at all, the widget now shows an
always-off icon instead of being hidden. That seemed the better default, but a
`Bluetooth.adapters.length === 0` hardware check could be used to hide it in that
case if preferred.

## Verification

Applied locally as a cloned plugin (`~/.config/omarchy/plugins/…-bluetooth/`),
with Bluetooth off and `/sys/class/bluetooth/` empty:

```
$ omarchy-shell omarchy.bluetooth toggleBluetooth     # adapter is null
$ rfkill list
0: tpacpi_bluetooth_sw: Bluetooth
	Soft blocked: no
$ ls /sys/class/bluetooth/
hci0
```

and toggling with the adapter present still runs `omarchy-bluetooth-power off`
as before. A full shell restart was required for the clone's edit to take effect;
the local-plugin hot-reload logged `Local plugin changed, reloading` but the
running panel kept the pre-edit code (worth a separate look).