fix styling issue on some devices

src/app/app.scss

@@ -26,4 +26,10 @@
     .toolbar-background {
         background: map-get($colors, primary);
     }
-}
+}
+
+// https://github.com/ionic-team/ionic/issues/16780
+// TODO: fixed in ionic-angular 3.9.3
+ion-content {
+  contain: size style;
+}