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A userscript that adds preview links to HTML files
// ==UserScript==// @name GitHub HTML Preview// @version 1.0.6// @description A userscript that adds preview links to HTML files// @license MIT// @author Rob Garrison// @namespace https://github.com/Mottie// @match https://github.com/*// @run-at document-idle// @grant none// @require https://greasyfork.org/scripts/28721-mutations/code/mutations.js?version=1108163// @require https://greasyfork.org/scripts/398877-utils-js/code/utilsjs.js?version=1079637// @icon https://github.githubassets.com/pinned-octocat.svg// @supportURL https://github.com/Mottie/GitHub-userscripts/issues// ==/UserScript==/* global $ $$ on */(() => {"use strict";// Example page: https://github.com/codrops/DecorativeLetterAnimations// Source: https://github.com/htmlpreview/htmlpreview.github.comconst prefix = "https://htmlpreview.github.io/?";// html & htm extensionsconst regex = /\.html?$/;const link = document.createElement("a");link.className = "ghhp-btn py-0 v-align-baseline tooltipped tooltipped-e";link.setAttribute("aria-label", "Open in new tab");link.target = "_blank";link.innerHTML = `<svg class="octicon v-align-text-bottom" xmlns="http://www.w3.org/2000/svg" width="14" height="14" viewBox="0 0 24 24" fill="currentColor"><path d="M19 19H5V5h7V3H5a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2v-7h-2v7zM14 3v2h3.59l-9.83 9.83 1.41 1.41L19 6.41V10h2V3h-7z"/></svg>`;link.style.marginRight = ".25rem";function addLink(el) {const cell = el.closest(".js-navigation-item div[role='rowheader'] span");if (cell && !$(".ghhp-btn", cell)) {const preview = link.cloneNode(true);preview.href = prefix + el.href;cell.prepend(preview);}}function init() {if ($("#files")) {const files = $("#files").parentElement;$$(".js-navigation-item div[role='rowheader'] .js-navigation-open", files).forEach(el => {if (regex.test(el.title)) {addLink(el);}});}}on(document, "ghmo:container", () => {// init after a short delay to allow rendering of file listsetTimeout(() => {init();}, 200);});init();})();