// ==UserScript==
// @name         Messenger Blacklist
// @namespace    AAAAAAAA.com
// @version      1.2
// @description  This is how you really block people
// @author       ducktrshessami
// @match        *://www.messenger.com/*
// @run-at       document-end
// @require      https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js
// @downloadURL none
// ==/UserScript==

(function() {
    const blacklist = [ // Fill this list with their Facebook names
        ""
    ];

    async function foo(selector) { // Do the thing
        var targets = $(selector + ":visible");
        if (targets.length) { // Target acquired
            targets.hide();
            console.log("Target destroyed");
        }
    }

    document.body.addEventListener("DOMNodeInserted", function() { // Wait for page change
        blacklist.forEach((name) => {
            if (name) {
                foo("[title^='Seen by " + name + " ']"); // Read receipt
                foo("[data-testid='info_panel'] > div > div > div > div > div > div > div > div > span > div > div > ul > li:has(:contains('" + name + "'))"); // Member list
                foo("[aria-label='Messages'] > div > div:has([alt='" + name + "'])"); // Message
            }
        });
    });
})();