Hello,
Thank you for using our plugin. The zoom-in feature is actually not a FSQM feature, rather an iOS browser feature. Even android has such feature. To disable it, you need to add the following meta tag inside the <head>...</head> portion of your theme:
<meta name="viewport" content="width=device-width, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no">
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