Button social media link in toolbar

Hello !

On my app ! I would like in the toolbar , the title, centered and a button link to the my LinkedIn page
but my problems are : the title is not centered when I put the button, and sometimes, it will be again centered ?
The second, is , when i click the button, it open linkedin, and immediatly it close linkedin for openning the page in my Safari app

Ionic version : 5.4.5

thx all !

<ion-header>
  <ion-toolbar class="new-background-color">
    <ion-buttons slot="start">
      <ion-menu-button></ion-menu-button>
    </ion-buttons>
    <ion-title class="ion-text-center" style="color:white">
      Accueil
    </ion-title>
    <ion-button class="ion-button-block-outline icon-only" fill="" color="transparent" class="ion-float-right" href="https://www.linkedin.com/company/xxxxx" target="blank_">
      <ion-icon name="logo-linkedin" class="ion-float-right" style="color:white"></ion-icon>
      </ion-button>
    </ion-toolbar> 
</ion-header>