Geolocation in webview app : how to change prompt text ?

Hi, I am creating an app for iOS with Xcode, which displays html files in a webview. For a page, I need geolocation of device and for this, I use geolocation HTML5.

Here is a part of my code : function detect_position(){ if (navigator.geolocation) { navigator.geolocation.getCurrentPosition( ... )

This works, but each time I open this page in my app (tested on simulator and physical device), I have this prompt : 

I am unable to change the text of this prompt to avoid this long folders tree. Any idea ? Thanks for your help.

Geolocation in webview app : how to change prompt text ?
 
 
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