In the file em_manager_helper there is a logic error that never resolves jsName or JsName_on. This is in the function _GetVarAttribute.

In the case JsName the logic is below:

return (isset($var['jsName_on']) ? $var['jsName_on'] : isset($var['jsName'])) ? $var['jsName'] : $default;

It has nested inline if statements. The first in line is passed to the next. The output of the first if is not a boolean "$var['jsName_on']", but the second is "isset($var['jsName'])". The whole statement is basically jacked up as it's a string as input into another if statement.

This isn't the only problem as the below code in the function setVariableAndTokenMappingsForExpressionManager always clears out js name on. So "isset($var['jsName_on'])" is always true and set to an empty string.

        // Hidden question are never on same page (except for equation)
        if ($hidden && $type != Question::QT_ASTERISK_EQUATION) {
            $jsVarName_on = '';
        }

I think the logic should be rewritten as follows :

if(isset($var['jsName']))
return $var['jsName'];
else if(isset($var['jsName_on']))
return $var['jsName_on'];
else
return $default;