ddg-verbatim.user.js

// ==UserScript==
// @name         DuckDuckGo Verbatim
// @namespace    https://github.com/josefandersson/userscripts/
// @version      1.1
// @description  Adds a verbatim button to the duckduckgo search bar
// @author       Josef Andersson
// @match        https://duckduckgo.com/*
// @run-at       document-end
// ==/UserScript==

if (location.pathname === '/') {
    const test = document.getElementById('content_homepage');
    if (test == null) {
        return;
    }

    let form = document.getElementById('search_form_homepage');
    let input = form.querySelector('input');

    form.addEventListener('submit', ev => {
        if (localStorage.getItem('forceVerbatim') === 'true') {
            input.value = input.value.replace(/([^ ]+)/g, '"$1"');
        }
    }, {
        capture: true
    });
    
    const div = document.createElement('div');
    const label = document.createElement('label');
    const checkbox = document.createElement('input');
    label.innerText = 'Verbatim';
    label.htmlFor = 'forceVerbatim'
    checkbox.id = 'forceVerbatim';
    checkbox.type = 'checkbox';
    checkbox.checked = localStorage.getItem('forceVerbatim') === 'true';
    div.appendChild(label);
    div.appendChild(checkbox);
    Object.assign(div.style, { margin:'-30px -3px 0 0', color:'#888', fontSize:'.8em', textAlign:'right' });
    Object.assign(checkbox.style, {})

    form.parentElement.insertBefore(div, form);

    checkbox.addEventListener('change', _ => {
        localStorage.setItem('forceVerbatim', checkbox.checked);
    });
}