I am parsing HTML page with fetch function and domParser. Among the script tags of this html page, there are some values ​​that I want to access, these are defined with the let variable. When I do console.log in Chrome, I can access these variables, but when I want to do it after parsing, I get a not defined error.

fetch(geturl)
           .then(function(response) {
               return response.text();
           })
           .then(function(html) {
               var parser = new DOMParser();
               var document = parser.parseFromString(html, "text/html");
               // Failed to fetch page: ReferenceError: test is not defined 
                  console.log(test);
           })
           .catch(function(error) {
               console.log("Error: ", error);
           });

<script>
let test ="test1234";
</script>