title: Safari heats up iPhone with iOS 11
body: <p>I found a strange behavior of Safari on iOS 11.<br><br>
  If I open <a href="https://vc.ru/30535-delimobil-predlozhil-klientam-peregnat-mashiny-iz-moskvy-v-sankt-peterburg-za-schet-kompanii" rel="nofollow noreferrer">any page</a> of <a href="https://vc.ru" rel="nofollow noreferrer">our website</a> on the same devices (tested for iPhones 5 and 6) but with different iOS versions: 10 and 11, then device with iOS 11 starts to heat up.<br><br>
  Using Safari timeline I found out that iOS 11 <em>(pic.1)</em>, unlike iOS 10 <em>(pic.2)</em>, produces many layout rendering events.<br>
  It's strange, considering that there's <strong>was no any user actions while the timeline was being recorded</strong>.<br><br>
  What could be reason for such behavior?</p>
  
  <p><a href="https://i.stack.imgur.com/7jjyl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7jjyl.png" alt="Pic.1: iOS 11"></a><em>Pic.1: iOS 11</em>
  <a href="https://i.stack.imgur.com/1m0yg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1m0yg.png" alt="Pic.2: iOS 10"></a><em>Pic.2: iOS 10</em></p>