No show menutoggle in navbar

Appflow
1 
<ion-header>
  <ion-navbar dir="rtl" hideBackButton="true">
    <ion-buttons start>
      <button ion-button icon-only>
        <ion-icon name="contact"></ion-icon>
      </button>
    </ion-buttons>
    <button ion-button menuToggle>
      <ion-icon name="menu"></ion-icon>
    </button>
    <ion-title>HI TEST</ion-title>
    <ion-buttons end>
      <button ion-button icon-only>
        <ion-icon name="search"></ion-icon>
      </button>
    </ion-buttons>
  </ion-navbar>

  <ion-toolbar>
    <ion-title>Subheader</ion-title>
  </ion-toolbar>
</ion-header>
2 
file :main.css
Line:4983

.hide,
[hidden],
template {
  display: none !important;
}