AdGuard DNS + Anti-Adblock Handler

Blocks ad/tracker domains and handles anti-adblock popups

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name        AdGuard DNS + Anti-Adblock Handler
// @description Blocks ad/tracker domains and handles anti-adblock popups
// @match       *://*/*
// @version 0.0.1.20251028121705
// @namespace https://greasyfork.org/users/1531587
// ==/UserScript==

(function() {
    'use strict';

    const FILTER_URL = "https://adguardteam.github.io/AdGuardSDNSFilter/Filters/filter.txt";
    const CACHE_KEY = "adguard_filter_cache";
    const CACHE_TIME_KEY = "adguard_filter_cache_time";
    const CACHE_TTL = 24 * 60 * 60 * 1000; // 24h
    let blockedDomains = [];

    async function loadFilterList() {
        const lastFetch = parseInt(localStorage.getItem(CACHE_TIME_KEY) || "0", 10);
        const now = Date.now();

        if (now - lastFetch < CACHE_TTL) {
            blockedDomains = JSON.parse(localStorage.getItem(CACHE_KEY) || "[]");
            console.log("[AdGuard] Loaded cached domains:", blockedDomains.length);
            return;
        }

        try {
            const res = await fetch(FILTER_URL);
            const text = await res.text();
            blockedDomains = text.split("\n")
                .filter(line => line.startsWith("||"))
                .map(line => line.replace("||", "").replace("^", "").trim());
            localStorage.setItem(CACHE_KEY, JSON.stringify(blockedDomains));
            localStorage.setItem(CACHE_TIME_KEY, now.toString());
            console.log("[AdGuard] Updated filter list:", blockedDomains.length);
        } catch (e) {
            console.warn("[AdGuard] Failed to fetch filter list", e);
            blockedDomains = JSON.parse(localStorage.getItem(CACHE_KEY) || "[]");
        }
    }

    // Block fetch requests
    const origFetch = window.fetch;
    window.fetch = function(input, init) {
        const url = typeof input === "string" ? input : input.url;
        if (blockedDomains.some(domain => url.includes(domain))) {
            console.warn("[AdGuard] Blocked fetch:", url);
            return Promise.reject("Blocked by AdGuard Userscript");
        }
        return origFetch.apply(this, arguments);
    };

    // Block XHR requests
    const origOpen = XMLHttpRequest.prototype.open;
    XMLHttpRequest.prototype.open = function(method, url) {
        if (blockedDomains.some(domain => url.includes(domain))) {
            console.warn("[AdGuard] Blocked XHR:", url);
            return;
        }
        return origOpen.apply(this, arguments);
    };

    // Remove ad elements dynamically
    const observer = new MutationObserver(() => {
        blockedDomains.forEach(domain => {
            document.querySelectorAll(`img[src*="${domain}"], iframe[src*="${domain}"], script[src*="${domain}"]`)
                .forEach(el => {
                    console.warn("[AdGuard] Removed element:", el.src);
                    el.remove();
                });
        });
    });
    observer.observe(document.documentElement, { childList: true, subtree: true });

    // Anti-Adblock detection
    function showAntiAdblockModal() {
        if (document.getElementById("adblock-modal")) return;
        const modal = document.createElement("div");
        modal.innerHTML = `
            <div id="adblock-modal" style="
                position: fixed; inset: 0;
                background: rgba(0,0,0,0.6);
                display: flex;
                align-items: center;
                justify-content: center;
                z-index: 999999;">
                <div style="
                    background: #fff;
                    padding: 20px 30px;
                    border-radius: 8px;
                    max-width: 400px;
                    text-align: center;
                    font-family: Arial, sans-serif;">
                    <h2 style="margin:0 0 10px; color:#e74c3c;">⚠ AdBlock Detected</h2>
                    <p style="margin:0 0 15px; font-size:15px; color:#333;">
                        This site detected you are using an Ad Blocker.<br>
                        Please disable it to continue smoothly.
                    </p>
                    <button id="disable-adblock-btn" style="
                        background:#e74c3c; color:#fff; padding:10px 20px;
                        border:none; border-radius:5px; font-size:14px; cursor:pointer;">
                        I Understand
                    </button>
                </div>
            </div>
        `;
        document.body.appendChild(modal);
        document.getElementById("disable-adblock-btn").addEventListener("click", () => {
            modal.remove();
        });
    }

    function antiAdblockWatcher() {
        const bait = document.createElement("div");
        bait.className = "ad ad-banner ad-unit adblock-detect";
        bait.style.position = "absolute";
        bait.style.left = "-9999px";
        document.body.appendChild(bait);

        setTimeout(() => {
            if (bait.offsetParent === null || bait.offsetHeight === 0 || bait.offsetWidth === 0) {
                showAntiAdblockModal();
            }
            bait.remove();
        }, 1500);
    }

    window.addEventListener("load", async () => {
        await loadFilterList();
        antiAdblockWatcher();
    });
})();