To Use this contrib with STS, couple of tweaks are necessary:

in modulesstssts_default.php find:

if (strstr($scriptbasename, "popup") || strstr($scriptbasename, "info_shopping_cart"))
return ''; // We don't use template for these scripts


replace with:

if (strstr($scriptbasename, "popup")|| strstr($scriptbasename, "ajaximage")|| strstr($scriptbasename, "info_shopping_cart"))
return ''; // We don't use template for these scripts


2) Make sure JS Script (the one is included usually in products_info.php) is included in STS template files (e.g. index.php.html and sts_default.php.html)

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