Custom Font Remover

custom-font-remover.user.js

// ==UserScript==
// @name     Custom Font Remover
// @version  2.1
// @include  http://*
// @include  https://*
// @grant    none
// ==/UserScript==

const GM_log = () => {};//unsafeWindow.console.log;
const BLACK_LIST = [
  "segoe ui", "meiryo", "system-ui", "-apple-system", "blinkmacsystemfont",
  "roboto", "helvetica", "arial", "inherit", 'freight sans bold',
  "hiragino kaku gothic pro", "ms pgothic", "helvetica neue", "segoe ui historic",
  "georgia", "sfprodisplay-bold", "sfprotext-semibold", "sfprotext-regular", ".sfnstext-regular",
	"menlo", "consolas", "monaco","google sans", "helveticaneue-light",
	"helveticaneue", "sans-serif-medium", "palatino linotype", "ヒラギノ角ゴ pro w3", "メイリオ",
  "ヒラギノ丸ゴ pro w4", "ヒラギノ丸ゴ pro", "hiragino maru gothic pro", "hg丸ｺﾞｼｯｸm-pro", "hgmarugothicmpro",
  "hiragino kaku gothic pro w3", "ｍｓ ｐゴシック", "biz udpgothic", "hiragino sans",
  "apple color emoji", "segoe ui emoji", "sfmono-regular", "sf mono", "liberation mono",
  "ui-monospace", "courier", "hiragino kaku gothic pron", "yu gothic", "tunga",
  "trebuchet ms", "tahoma", "verdana", "lucida grande", "andale mono",
  "dejavu sans mono", "arial black", "Impact", "open sans", "ヒラギノ角ゴシック",
  "ヒラギノ角ゴ pron w3", "droid sans", "yugothic", "游ゴシック", "courier new",
  "arialmt", "osaka", "hirakakupron-w3", "ms ui gothic", "hgｺﾞｼｯｸm",
  "noto sans", "segoe ui symbol", "noto color emoji", "droid sans mono", "biz udgothic",
  "meiryo ui", "游ゴシック medium", "yu gothic medium", "ヒラギノ角ゴ pro"
];

const cleanFont = function(tag) {
  const fontRules = Array.from(document.styleSheets)
      .flatMap(s => {
        try {
          return Array.from(s.rules);
        } catch (e) {
          return null;
        }
      })
      .filter(r => r != null && typeof r.style != "undefined")
      .filter(r => r.style.fontFamily != "" && typeof r.style.fontFamily != "undefined");
  var clean = false;
  fontRules.forEach(rule => {
    const original = rule.style.fontFamily;
    const modified = original.split(/, ?/)
      	.filter(f => BLACK_LIST.indexOf(f.toLowerCase().replaceAll(/["']/g, "")) == -1)
      	.join(", ");
    if (original != modified) {
      clean = true;
      rule.style.fontFamily = modified;
      if (modified != "" && modified != "sans-serif" && modified != "serif" && modified != "monospace") {
        GM_log("[on" + tag + "] Modified: " + rule.selectorText + " { font-family: " + modified + "; }");
      }
    }
  });
  const weightRules = Array.from(document.styleSheets)
  		.flatMap(s => {
        try {
          return Array.from(s.rules);
        } catch (e) {
          return null;
        }
      })
      .filter(r => r != null && typeof r.style != "undefined")
      .filter(r => r.style.fontWeight == "lighter" || (/^[0-9]+$/.test(r.style.fontWeight) && parseInt(r.style.fontWeight) < 400));
  weightRules.forEach(rule => {
    rule.style.fontWeight = "";
    clean = true;
  });
  const spacingRules = Array.from(document.styleSheets)
  		.flatMap(s => {
        try {
          return Array.from(s.rules);
        } catch (e) {
          return null;
        }
      })
      .filter(r => r != null && typeof r.style != "undefined")
      .filter(r => r.style.letterSpacing != "" && typeof r.style.letterSpacing != "undefined");
  spacingRules.forEach(rule => {
    rule.style.letterSpacing = "";
    clean = true;
  });
  if (clean) {
  	GM_log("[on" + tag + "] Font cleanup successfuly finished.");
  }
};

window.addEventListener("load", () => { cleanFont("Load") });
cleanFont("Init");

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