我在codepen中复制了你的代码，它工作得很好，只是URL上的端口，没有顶级域（RegEx没有拾取的顶级域）。
将代码与常规格式的URL一起使用可以正常工作。
Working Codepen Example

import dompurify from "https://esm.sh/dompurify";
import React from "https://esm.sh/react";
import ReactDOM from "https://esm.sh/react-dom";

const Linkify = ({ children }) => {
  const isUrl = (word) => {
    const urlPattern = /^(http:\/\/www\.|https:\/\/www\.|http:\/\/|https:\/\/)?[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}(:[0-9]{1,5})?(\/.*)?$/gm;
    return word.match(urlPattern);
  };

  const addMarkup = (word) => {
    return isUrl(word)
      ? `<a class="text-blue-500 hover:text-blue-600 transition" href="${word}">${word}</a>`
      : `<span className="no-underline">${word}</span>`;
  };

  const words = children.split(" ");
  const formatedWords = words.map((w, i) => addMarkup(w));

  const html = dompurify.sanitize(formatedWords.join(" "));

  return <span dangerouslySetInnerHTML={{ __html: html }} />;
};

const Test = () => {
  return (
    <div>
      <Linkify>
        Add a URL in here, for example, http://www.google.com/ -- look's good!
      </Linkify>
    </div>
  );
};

const root = ReactDOM.createRoot(document.getElementById("app"));

root.render(<Test />);

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欢呼

好吧，我找到了我的问题的答案，这里是检测所有链接的代码：

import dompurify from "dompurify";

// detects every link now
const Linkify = ({ children }) => {
  const isUrl = (word) => {
    const urlPattern = /(https?:\/\/[^\s]+)/g;
    return word.match(urlPattern);
  };

  const addMarkup = (word) => {
    return isUrl(word)
      ? `<a class="text-blue-500 hover:text-blue-600 transition" href="${word}">${word}</a>`
      : `<span className="no-underline text-white">${word}</span>`;
  };

  const words = children.split(" ");
  const formatedWords = words.map((w, i) => addMarkup(w));

  const html = dompurify.sanitize(formatedWords.join(" "));

  return <span dangerouslySetInnerHTML={{ __html: html }} />;
};

export default Linkify

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