Ionic Page laggs on first Launch on iPhone first time

Ionic Framework
1

I have a blanc ionic 4 project.
My ionic versions are:

Ionic:

ionic (Ionic CLI) : 4.12.0 (/usr/local/lib/node_modules/ionic)
Ionic Framework : @ionic/angular 4.3.1
@angular-devkit/build-angular : 0.13.8
@angular-devkit/schematics : 7.3.8
@angular/cli : 7.3.8
@ionic/angular-toolkit : 1.5.1

Capacitor:

capacitor (Capacitor CLI) : 1.0.0-beta.19
@capacitor/core : 1.0.0-beta.19

System:

NodeJS : v11.2.0 (/usr/local/bin/node)
npm : 6.9.0
OS : macOS Mojave

With Capacitor i deploy the app on my iPhone. It works normal.

image
image432×817 34.9 KB

Now i add in the Page an ion-refresher like


<ion-content>
  <ion-refresher>
    <ion-refresher-content
            pullingIcon="arrow-dropdown"
            pullingText="Pull to refresh"
            refreshingSpinner="circles"
            refreshingText="Refreshing...">
    </ion-refresher-content>
  </ion-refresher>

  <ion-list>
    <ion-item *ngFor="let item of items">
      <ion-icon [name]="item.icon" slot="start"></ion-icon>
      {{item.title}}
      <div class="item-note" slot="end">
        {{item.note}}
      </div>
    </ion-item>
  </ion-list>
</ion-content>

Now the Page laggs on the first launch on my iPhone. Android and Browser it is okay.

Whats my mistake?