convert a non-http url to url

my iphone app downloads maps from a website which uses the following for the download link.

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Apparently fetch won't let my app download without the http(s) prefix.

How can the link be captured so I can add a http prefix?

The links work okay when using a browser on iPad/phone/imac but not when using WKWebkit.

Thanks

convert a non-http url to url
 
 
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