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Fix Fanbox external links.user.js

// ==UserScript==
// @name         Fix Fanbox external links
// @namespace    https://www.fanbox.cc/
// @version      1.0
// @description  This script fix Mega links at the moment
// @author       X4
// @match        https://*.fanbox.cc/posts/*
// @match        https://*.fanbox.cc/@*/posts/*
// @icon         https://icons.duckduckgo.com/ip2/fanbox.cc.ico
// @grant        none
// ==/UserScript==

(async () => {
	"use strict";

	const wait_for_el = (selector) => {
		return new Promise(resolve => {
			if (document.querySelector(selector)) {
				return resolve(document.querySelector(selector));
			}

			const observer = new MutationObserver(mutations => {
				if (document.querySelector(selector)) {
					resolve(document.querySelector(selector));
					observer.disconnect();
				}
			});

			observer.observe(document.body, {
				childList: true,
				subtree: true
			});
		});
	}

	const p = await wait_for_el(".public-DraftEditor-content > div");

	for (const s of p.querySelectorAll("span[data-text]")) {
		if (!/\b(?<!\/)[\w\-_]{8}#[\w\-_]{22}\b/.test(s.innerHTML)) continue;

		s.innerHTML = s?.innerHTML?.replace?.(
			/\b(?<!\/)[\w\-_]{8}#[\w\-_]{22}\b/g,
			`<a href="https://mega.nz/folder/$&">https://mega.nz/folder/$&</a>`
		);
	}
})();