badge on the hamburger menu ?

            ->renderHook(
                PanelsRenderHook::TOPBAR_START,
                function () : string {

                    if (Filament::getTenant()->hasAlerts()) {
                        return Blade::render('@livewire(\'area.persona.livewire.sidebar-alert\')');
                    }

                    return '';
                }

            )

use Livewire\Component;

class SidebarAlert extends Component
{
    public function render()
    {
        return view('web.components.panel.persona.sidebar.alert');
    }
}

<div class="lg:hidden">
        <x-filament::icon-button
            type="button"
            wire:loading.attr="disabled"
            x-on:click="$store.sidebar.open()"
            x-show="! $store.sidebar.isOpen"
            icon="phosphor-caret-circle-double-right-duotone"
            size="lg"
            class="animate-pulse text-red-500"
            tooltip="You have alerts, expand the sidebar to see them"
        />
</div>