Add reddit-hide-sidebar.

reddit-hide-sidebar/index.js

+// ==UserScript==
+// @name         old.reddit hide sidebar
+// @namespace    http://tampermonkey.net/
+// @version      1.0
+// @description  Adds toggle to hide Reddit sidebar
+// @author       hugo@lysator.liu.se
+// @match        https://old.reddit.com/*
+// @match        https://www.reddit.com/r/*/wiki/*
+// @match        https://www.reddit.com/*
+// @grant        GM_addStyle
+// @require      https://code.jquery.com/jquery-3.3.1.min.js
+// ==/UserScript==
+
+(function() {
+    'use strict';
+
+    var visible = true;
+
+    let btn = $("<button>&gt;</button>");
+    let div = $("<div class='sidebar-toggle'></div>")
+
+    div.append(btn)
+    $("#header").append(div);
+
+    let sidebar = $(".side");
+    let speed = 500;
+    var active = false;
+
+    btn.click(function(ev) {
+        if (active) return;
+        active = true;
+        if (visible) {
+            sidebar.hide(speed, function () {
+                active = false;
+                btn.text("<");
+            });
+        } else {
+            sidebar.show(speed, function () {
+                active = false;
+                btn.text(">");
+            });
+        }
+        visible = !visible;
+    });
+
+    GM_addStyle(" \
+.sidebar-toggle { \
+    position: absolute; \
+    z-index: 100; \
+    right: 0; \
+    bottom: 0; \
+} \
+.sidebar-toggle > button { \
+    width: 25px; \
+    height: 25px; \
+}");
+})();