JSFiddle - React, Tailwind, and code Playground

JavaScript

var html = '\n\n<span id="sc_start_commenttext-330"></span>\n\n \
Text and code to give back\n\n \
\n\n<span id="sc_end_commenttext-330"></span>\n\n';

alert( 
    html.replace(/(<span id="sc_start_commenttext-(\d+)"><\/span>)[\S\s.]*?(<span id="sc_end_commenttext-\2"><\/span>)/, "$1$3") 
);