Safari hangs downloading javascript, fonts or css (@imports)

Originator:goncalo.borrega
Number:rdar://24759326 Date Originated:2015/02/21
Status:Open Resolved:
Product:iOS Product Version:9.2.1
Classification:Crash/Hang/Data Loss Reproducible:yes
 
Summary:
In devices running iOS 9+, in Safari, while retrieving all page resources, the browser hangs for around 10-30 seconds, until it finally unblocks and the resources are downloaded (and loaded/executed as usual)


Steps to Reproduce:
Create a webpage with the following content and host it in any webserver

<html>
	<head>
		<title>iOS 9 - 30 seconds slowliness</title>
	</head>
	<body>
		<img src="fruit1.png"/>	
		<img src="fruit2.png"/>
		<img src="fruit3.png"/>
		<img src="fruit4.png"/>
		<img src="fruit5.png"/>
		<img src="fruit6.png"/>
		<script src="EmptyJavaScript.js" type="text/javascript" ></script>
	</body>
</html>

The image files can be whatever you want.
The javascript file can contain whatever you want (adding a simple alert('BLA') creates a simple scenario

Expected Results:
simple loading of the page + javascript resource.

Actual Results:
Safari hangs for ~30s when loading the javascript file. 
Independently of its content (put an "alert('bla')" inside....)


Version:
iOS 9.2.1

Notes:


Configuration:
iPhone 6 using wifi

Attachments:

Comments


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