async function loadBootstrap(showMessage = false) {
  if (app.loading) return;
  app.loading = true;
  try {
    const [data, sections] = await Promise.all([api('/api/bootstrap'), fetchSettingsSections()]);
    app.devices = data.devices || [];
    app.zones = data.zones || [];
    app.groups = data.groups || [];
    app.schedules = data.schedules || [];
    app.automations = data.automations || [];
    app.flows = data.flows || [];
    app.accessTokens = data.access_tokens || [];
    app.settings = aggregateSettingsSections(sections, data.house?.mode || 'cool');
    app.sensorAliases = { ...(app.settings.home_assistant?.sensor_aliases || {}) };
    app.flowSharedInputs = JSON.parse(JSON.stringify(app.settings.home_assistant?.flow_inputs || []));
    app.system = data.system || {};
    app.systemSnapshotAt = Date.now();
    app.outdoorTemperature = Number.isFinite(Number(data.outdoor_temperature)) ? Number(data.outdoor_temperature) : null;
    renderAll();
    loadControlPlan();
    if (app.settings?.debug?.overlay_enabled) loadDebugBacklog();
    if (showMessage) toast(tr('common.updated'));
    if ($('#tokenDialog').open) $('#tokenDialog').close();
    connectWebSocket();
  } catch (error) {
    if (!String(error.message).toLowerCase().includes('token')) toast(error.message, true);
  } finally {
    app.loading = false;
  }
}