title: Stripe js UI not showing on IOS PWA
body: <p>I have used pwa builder to create an iOS app.  Everything works perfect except for the Stripe UI on the credit card form.  On the app it shows a blank input field but when viewed in Chrome, Safari etc it shows the correct placeholder (ie. Card Number     MM/YYY).</p>
  
  <p>I've tried changing the manifest.json display option from standalone to fullscreen (as suggested <a href="https://github.com/paypal/paypal-checkout-components/issues/699" rel="nofollow noreferrer">https://github.com/paypal/paypal-checkout-components/issues/699</a>) but no luck.  </p>
  
  <p>I also tinkered with the stripe-charge.js script src link incase there was an issue with that when in the PWA shell but hasn't made a difference.</p>
  
  <p>No js errors appear when viewing on browser so assuming it has something to do with what iOS does pulling a website into an app frame.</p>
  
  <pre><code>               &lt;div id='card-element'&gt;
                   &lt;!-- a Stripe Element will be inserted here. --&gt;
                 &lt;/div&gt;
                 &lt;!-- Used to display form errors --&gt;
                 &lt;div id='card-errors'&gt;&lt;/div&gt;
             &lt;/div&gt;
             &lt;input type='hidden' name='stripeEmail' value='&lt;? echo $user_email; ?&gt;' /&gt;
             &lt;button name='payment-form' class='cta_std__v4 _std__black'&gt;Complete&lt;/button&gt;
         &lt;/form&gt;
         &lt;script src='https://js.stripe.com/v3/'&gt;&lt;/script&gt;
         &lt;script src='/public/_asset/_js/stripe-charge.js'&gt;&lt;/script&gt;
  </code></pre>