Strange ion-label splash artifact at android

Ionic Framework ionic-v3
1

Hello All, i have an app which were built for IOS device, now i run it under android device (sams note N915), and noticed strange blink of ion-label of ion-input with same frequency as coursor blinks

2

here video https://drive.google.com/open?id=1QWqykoIbSvEDA1jhMwBShk_oQlAkJ1dE

3

also code

<ion-header>
    <ion-navbar>
        <ion-title>Signup with MMM account</ion-title>
    </ion-navbar>
</ion-header>
<ion-content style='background-image: url("assets/img/map.png");background-size:cover;'>
    <ion-card offset-md-2 col-12 col-xs-12 col-sm-12 col-md-8 col-lg-6 col-xl-6 style="margin-top:0;padding-top:0;">
        <ion-grid>
            <ion-row justify-content-center justify-content-start>
                <ion-col col-10 col-xs-10 col-sm-10 col-md-10 col-lg-10 col-xl-10>
                    <form #loginForm="ngForm" novalidate>
                        <ion-label stacked>Username</ion-label>
                        <ion-input #username type="text" placeholder="{{placeholderU}}"></ion-input>
                        <ion-label stacked>Password</ion-label>
                        <ion-input #password type="password" placeholder="{{placeholderP}}"></ion-input>
                        <button ion-button round (click)="onSave(username.value, password.value)" type="submit" color="primary" outline
                                style="margin:2vh 1vw 0 0;">Signup
                        </button>
                    </form>
                </ion-col>
            </ion-row>
        </ion-grid>
    </ion-card>
</ion-content>