Method floatPanadapter

src/gui/PanadapterStack.cpp:699–745

// ── Float / Dock ──────────────────────────────────────────────────────────

void PanadapterStack::floatPanadapter(const QString& panId)
{
    PanadapterApplet* applet = m_pans.value(panId, nullptr);
    if (!applet || m_floatingWindows.contains(panId)) return;

    // Hide the SpectrumWidget and release GPU resources *before* reparenting.
    // On macOS, QRhiWidget with WA_NativeWindow has a native NSView; orphaning
    // the widget to nullptr creates a transient top-level NSWindow whose
    // destruction can corrupt the main window's NSResponder chain (#1344).
    SpectrumWidget* sw = applet->spectrumWidget();
    sw->hide();
    sw->prepareForTopLevelChange();
    sw->resetGpuResources();

    // Reparent directly from splitter into the floating window — never through
    // nullptr. Using adoptApplet() calls addWidget() internally which sets
    // the parent to the floating window in one step, avoiding the transient
    // top-level NSWindow that corrupts the NSResponder chain (#1668).
    // Parenting the floating window to MainWindow keeps it on top of the
    // main window without becoming WindowStaysOnTopHint (which would
    // float above other apps too).  Qt::Window inside PanFloatingWindow
    // keeps it as a top-level window — the parent only affects z-order
    // and lifetime.
    auto* fw = new PanFloatingWindow(window());
    fw->adoptApplet(applet);
    applet->spectrumWidget()->setFloating(true);

    m_floatingWindows[panId] = fw;
    rebuildDockedSplitter();
    fw->restoreWindowGeometry();
    fw->show();
    fw->raise();
    saveFloatingState();
    emit panFloated(panId);

    connect(fw, &PanFloatingWindow::dockRequested,
            this, &PanadapterStack::dockPanadapter);

    // Defer sw->show() until after refreshAfterReparent() so Metal binds to
    // the new NSView before the first render. Showing before the reset can
    // trigger render() on a stale/transitional Metal surface.
    QTimer::singleShot(0, this, [this, sw]() {
        refreshAfterReparent(sw);
        sw->show();
        equalizeSizes();
    });
}

void PanadapterStack::dockPanadapter(const QString& panId)
{