dbdl.js

// ==UserScript==
// @name           Derpibooru Quick Downloader
// @version        1.0
// @description    display the DS (download with a short name) button over the thumbnail in search results
// @author         Scriptki77y
// @include        https://derpibooru.org/*
// @include        http://derpibooru.org/*
// @run-at document-end
// ==/UserScript==

var parser = new DOMParser()
elements = document.querySelectorAll('#imagelist_container .media-box__header.media-box__header--link-row')
elements3 = document.querySelectorAll('#imagelist_container .thumb')
for(let i = 0; i < elements.length ; ++i)
{
url = JSON.parse(elements3[i].dataset.uris).large
elements[i].appendChild(generate_button(url.replace('img', 'img/download').replace('/large', '')))
}
function generate_button(url) {
    let node = parser.parseFromString(`
    <a rel="nofollow" 
    title="Download this image at full res with a short filename"
href="${url}">
<i class="fa fa-download"></i> DS</a>
`, "text/html").body.childNodes[0];
    return node;
};