Replace twitter ugly font in Chinese

twitter-font-beauty.js

// ==UserScript==
// @name         Twitter font beauty
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Replace twitter ugly font in Chinese!
// @author       Bill Chan
// @match        https://twitter.com/*
// @icon
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    var rule = `div[data-testid="tweetText"] > span {
        font-family: system-ui !important;
    }`;
    var styleElement = document.createElement("style");

    styleElement.type = "text/css";

    if (styleElement.style.cssText) {
        styleElement.style.cssText = rule;
    } else {
        styleElement.appendChild(document.createTextNode(rule));
    }

    document.getElementsByTagName("head")[0].appendChild(styleElement);
})();