title: Ionic 5 - ASSERTION ERROR: Expecting flags
body: <p>I tried creating another page and modifying the paths but the error only appears when an ion-tabs is present.</p>
  <p>And if I remove the <strong>component: MenuPage</strong>, the page works normally (without the tabs)</p>
  <p><strong>menu-routing.module.ts</strong> :</p>
  <pre><code>const routes: Routes = [
    {
      path: '',
      component: MenuPage,
      children: [
        {
          path: 'list',
          loadChildren: () =&gt; import('../list/list.module').then(m =&gt; m.ListPageModule),
        },
        {
          path: '',
          redirectTo: '/menu/list',
          pathMatch: 'full',
        },
      ],
    },
    {
      path: '',
      redirectTo: '/menu/list',
      pathMatch: 'full',
    },
  
  ];
  
  </code></pre>
  <p><strong>menu.page.html</strong> :</p>
  <pre><code>&lt;ion-content&gt;
    &lt;ion-tabs&gt;
      &lt;ion-tab-bar slot=&quot;bottom&quot;&gt;
  
        &lt;ion-tab-button tab=&quot;list&quot;&gt;
          &lt;ion-icon name=&quot;home-outline&quot;&gt;&lt;/ion-icon&gt;
          &lt;ion-label&gt;Home&lt;/ion-label&gt;
        &lt;/ion-tab-button&gt;
  
        &lt;ion-tab-button&gt;
          &lt;ion-icon name=&quot;settings&quot;&gt;&lt;/ion-icon&gt;
          &lt;ion-label&gt;Settings&lt;/ion-label&gt;
        &lt;/ion-tab-button&gt;
  
      &lt;/ion-tab-bar&gt;
    &lt;/ion-tabs&gt;
  &lt;/ion-content&gt;
  </code></pre>
  <p><strong>Error</strong>:</p>
  <pre><code>ERROR Error: Uncaught (in promise): Error: ASSERTION ERROR: Expecting flags [Expected=&gt; number === boolean &lt;=Actual]
  Error: ASSERTION ERROR: Expecting flags [Expected=&gt; number === boolean &lt;=Actual]
      at throwError (core.js:210)
      at assertNumber (core.js:141)
      at Module.ɵɵcontentQuery (core.js:26536)
      at Object.IonTabs_ContentQueries [as contentQueries] (ionic-angular.js:3143)
      at executeContentQueries (core.js:9554)
      at ɵɵelementStart (core.js:14788)
      at MenuPage_Template (template.html:2)
      at executeTemplate (core.js:9538)
      at renderView (core.js:9345)
      at renderComponent (core.js:10620)
      at resolvePromise (zone-evergreen.js:798)
      at resolvePromise (zone-evergreen.js:750)
      at zone-evergreen.js:860
      at ZoneDelegate.invokeTask (zone-evergreen.js:399)
      at Object.onInvokeTask (core.js:28515)
      at ZoneDelegate.invokeTask (zone-evergreen.js:398)
      at Zone.runTask (zone-evergreen.js:167)
      at drainMicroTaskQueue (zone-evergreen.js:569)
      at ZoneTask.invokeTask [as invoke] (zone-evergreen.js:484)
      at invokeTask (zone-evergreen.js:1621)
  </code></pre>
  <p>EDIT:
  They are completely empty, don't add code actually</p>
  <p><strong>Menu.module.ts</strong></p>
  <pre><code>@NgModule({
    imports: [
      IonicModule,
      CommonModule,
      FormsModule,
      MenuPageRoutingModule
    ],
    declarations: [MenuPage]
  })
  export class MenuPageModule {}
  </code></pre>
  <p><strong>menu.page.ts</strong>:</p>
  <pre><code>@Component({
    selector: 'main-menu',
    templateUrl: './menu.page.html',
    styleUrls: ['./menu.page.scss'],
  })
  export class MenuPage {}
  </code></pre>
  <p>I don't know what to do.</p>