Test external font display on ios iphone

-> With highcharts latest version 5.0.14

HTML

<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<link href="https://fonts.googleapis.com/css?family=Gloria+Hallelujah" rel="stylesheet">
<script src="https://code.jquery.com/jquery-3.2.1.min.js" integrity="sha256-hwg4gsxgFZhOsEEamdOYGBf13FyQuiTwlAQgxVSNgt4=" crossorigin="anonymous"></script>
<script type="text/javascript" src="https://github.highcharts.com/f23971ed12ceaa4cfc572f5d781e9823f6b37bbc/highcharts.src.js"></script>

<div id="container"></div>

JavaScript

Highcharts.theme = {
   lang: {
     decimalPoint: ",",
     loading: "Chargement...",
     months: ['Janvier', 'Février', 'Mars', 'Avril', 'Mai', 'Juin', 'Juillet', 'Août', 'Septembre', 'Octobre', 'Novembre', 'Décembre'],
     weekdays: ['Dimanche', 'Lundi', 'Mardi', 'Mercredi', 'Jeudi', 'Vendredi', 'Samedi'],
     shortMonths: ['Jan.', 'Fév.', 'Mars', 'Avr.', 'Mai', 'juin', 'Juil.', 'Août', 'Sept.', 'Oct.', 'Nov.', 'Déc.']
   },
   colors: ["#ff9e0f", "#3C7ACC", "#BBD0E5", "#B2AE9C", "#D3D1C4", "#81312F", "#CE1515", "#CE1515", "#003872", "#FF9900"],
   chart: {
     backgroundColor: null,
     style: {
       fontFamily: "\'Gloria Hallelujah\',cursive"
     }
   },
   title: {
     style: {
       fontSize: '15px',
       fontWeight: 400
     }

   },
   legend: {
     itemStyle: {
       fontWeight: 'bold',
       fontSize: '14px'
     }
   },
   xAxis: {
     gridLineWidth: 0,
     labels: {
       style: {
         fontSize: '12px'
       }
     }
   },
   yAxis: {
     minorTickInterval: 'auto',
     title: {
       style: {
         textTransform: 'uppercase'
       }
     },
     labels: {
       style: {
         fontSize: '13px'
       }
     }
   },
   plotOptions: {
     candlestick: {
       lineColor: '#404048'
     },
     /*Add since highchart change to 5.0 by Teatis, because the default template changed to better rendering chart*/
     series: {
       dataLabels: {
         style: {
           fontSize: '13px'
         }
       }
     }
   },
   /*Add since highchart change to 5.0 by Teatis, because the default template changed to better rendering chart*/
   tooltip: {
     style: {
       fontSize: '13px'
     },
     headerFormat: '<span style="font-size: 11px">{point.key}</span><br/>'
   },

   // General
   background2: '#F0F0EA'
 };

 // Apply the theme
 Highcharts.setOptions(Highcharts.theme);

 Highcharts.chart('container', {
   exporting: {
     enabled: false
   },
   chart: {
     plotBackgroundColor: null,
     plotBorderWidth:...