If this is definitely just stored as a string you can do the following...
var element = $(myString);//convert string to JQuery element
element.find("span").remove();//remove span elements
var newString = element.html();//get back new string
if in fact this is already rendered html in your page then just do...
$("span").remove();//remove span elements (all spans on page as this code stands)
If you want to keep the contents of the span tag you can try this...
var element = $(myString);//convert string to JQuery element
element.find("span").each(function(index) {
var text = $(this).text();//get span content
$(this).replaceWith(text);//replace all span with just content
});
var newString = element.html();//get back new string
Here is a working example (you will see two alerts: string at start, string at end)
You can also just do this which might get the result you need:
var justText = $(myString).text();
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