Ionic 5: UI glitches in landscape mode

I am experiencing UI glitches when transitioning from portrait mode to landscape mode by flipping my physical phone around.

In portrait modus, everything looks fine.

In landscape mode, black blocks appear instead of the ion-input fields. Upon scrolling in landscape mode, the UI may re-appear, but it looks off.

I already tried "build > clean project "in Android Studio.

I took the code of the ionic Starter App:

<form [formGroup]="loginForm" (ngSubmit)="doEmailLogin()">
    <ion-list class="inputs-list" lines="full">
      <ion-item class="input-item">
        <ion-input
          type="email"
          placeholder="Email"
          formControlName="email"
          clearInput
          autocapitalize="off"
          inputmode="email"
        ></ion-input>
      </ion-item>
...