talktalk-webmail-fixer.user.js

// ==UserScript==
// @name         TalkTalk Webmail Fixer
// @namespace    https://gist.github.com/huwcbjones/6afb06aee8734e2f4f3c40794c5e1386
// @version      0.1
// @description  Fix webmail view on talktalk
// @author       huwcbjones
// @match        *://apps.talktalk.co.uk/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    window.setTimeout( function() {
        let rightSideBar = document.getElementsByClassName("io-ox-ads-skyscraper right")[0];
        let mainWindow = document.getElementsByClassName("window-body classic-toolbar-visible")[0];

        if (rightSideBar !== undefined) rightSideBar.remove();
        if (mainWindow !== undefined) {
            mainWindow.style.setProperty("bottom", 0, "important")
        }
    }, 4500);

})();