19/07/23 13:54:12.13 ls/fpQRk0.net
Tampermonkeyとかでできる
(function() {
'use strict';
let html = document.getElementsByTagName("html")[0].innerHTML;
html = html.replace(/名無しさん/g, "hogehoge");//ここで好きなように置換
document.getElementsByTagName("html")[0].innerHTML = html;
})();