The problem occurs on the iPhone with IOS versions 12.3.1 and 12.3.2.
The App uses a Webview component to display HTML5 pages with scripts.
In one of the HTML pages we have the <video> tag that loads videos in .mp4 and the <track> attribute loads a .VTT subtitle file.
When the video is executed, the subtitle (vtt) is showed, and after a few seconds (between 5 and 15 seconds) the App crash.
In all the tests we've done, we've concluded that what causes the App to crash is the subtitle.
NO problem occurs with videos WITHOUT subtitles.
To see the problem you can install App "Mindquest" and access it.
login: apple@ / password: apple
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