jsfiddle annoyaces userscript

jsfiddle-annoyances.user.js

// ==UserScript==
// @name         jsfiddle annoyances
// @namespace    https://gist.githubusercontent.com/thykka/d130a68229dc9bda81e6f11f7388d52d/
// @version      0.0.3
// @description  Kill the anti-features!
// @author       Thykka
// @match        https://jsfiddle.net/*
// @updateURL    https://gist.githubusercontent.com/thykka/d130a68229dc9bda81e6f11f7388d52d/raw
// @downloadURL  https://gist.githubusercontent.com/thykka/d130a68229dc9bda81e6f11f7388d52d/raw
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const styleString = `
#s-bottom,
#keep-us-running.show,
#hello-bar {
  display: none!important;
}

header {
  height: 1.75rem;
}

#sidebar {
  background: #eee;
  top: 1.75rem;
  z-index: 0;
}

body[data-skeleton-url*="dark.css"] #sidebar { background: #000; }

#editor {
  height: calc(100vh - 1.75rem) !important;
  display: flex;
  flex-flow: row nowrap;
  width: 100%;
}

#editor > .panel-v {
  float: none;
  flex: 0 0 auto;
}

#sidebar:hover { background: #333; }
body[data-skeleton-url*="dark.css"] #sidebar:hover { background: #f0f0f0; }

#sidebar:hover + #content {
  transform: translateX(210px);
}

#content {
  background: #f8f8f8;
  transition: transform 0.5s 0.25s ease-out;
  margin-left: 4px;
}
body[data-skeleton-url*="dark.css"] #content { background: #111; }

#content .windowSettings {
  left: 2rem !important;
  right: 2rem !important;
  max-width: 20rem;
  width: 100%;
}

#editor .CodeMirror-gutters {
  background-color: #fff;
}
body[data-skeleton-url*="dark.css"] #editor .CodeMirror-gutters {
  background-color: #000;
}

#editor .windowLabel {
  line-height: 1;
  padding: 4px 0 4px 60px;
}

#editor .CodeMirror {
  height: calc(100% - 20px);
  margin-top: 20px;
}

#actions {
  display: flex;
  flex-flow: row nowrap;
  justify-content: space-between;
  margin-right: 0.5rem;
}
#actions .actionCont {
  float: none;
  display: flex;
  flex-flow: row nowrap;
  justify-content: space-around;
  flex: 1 0 auto;
}

#actions .actionItem {
  float: none;
  white-space: nowrap;
}
#actions #usermenu {
  padding-left: 0;
}
#actions #usermenu img,
header h1 {
  top: 8px;
}
#actions #usermenu img,
header h1 svg {
  position: relative;
  height: 1em;
  width: auto;
  vertical-align: top;
}
#actions .actionItem a.aiButton {
  padding: 0;
}

#actions,
#actions .actionItem .aiButton,
#actions .actionItem .aiButton span,
#actions .dropdown .actionItem a.aiButton {
  height: auto;
}
#actions .actionItem a.aiButton {
  line-height: 2;
}

@media screen and (max-width: 680px) {
  #actions .actionItem a.aiButton {
    width: 1.5rem;
    overflow-x: hidden;
  }
}

#progressbar {
  top: 0;
}
#app-updates.hidden {
  display: none;
}
`;
    const styleEl = document.createElement('style');
    styleEl.innerHTML = styleString;

    document.head.appendChild(styleEl);

})();

Compact main view
Thin screen view
Hidden sidebar