code-input.component.html

<mat-card fxFlex="0 0 400px">
  <form [formGroup]="codeinputform" (ngSubmit)="codeinput()">
    <mat-card-title>{{ 'login_codeInputTitle' | customtext:'login_codeInputTitle':cts.updateCount }}</mat-card-title>
    <mat-card-subtitle>{{ 'login_codeInputPrompt' | customtext:'login_codeInputPrompt':cts.updateCount }}</mat-card-subtitle>
    <mat-card-content>
      <mat-form-field>
        <input matInput formControlName="code" (keyup.enter)="codeinput()"> <!-- no placeholder! -->
      </mat-form-field>
    </mat-card-content>
    <mat-card-actions>
      <button mat-raised-button type="submit" [disabled]="codeinputform.invalid" color="primary">Weiter</button>
      <button mat-raised-button color="foreground" (click)="resetLogin()">Neu anmelden</button>
    </mat-card-actions>
  </form>
</mat-card>