diff --git a/mozilla/firefox/userContent.css b/web/firefox/userContent.css
similarity index 100%
rename from mozilla/firefox/userContent.css
rename to web/firefox/userContent.css
diff --git a/web/userscripts/README.md b/web/userscripts/README.md
new file mode 100644
index 0000000..c118d98
--- /dev/null
+++ b/web/userscripts/README.md
@@ -0,0 +1 @@
+[Tampermonkey](https://www.tampermonkey.net/) ([Firefox extension](https://addons.mozilla.org/en-US/firefox/addon/tampermonkey/), [Chrome extension](https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo)) is recommended for loading these as it supports installing and updating userscripts from a remote URL.
diff --git a/web/userscripts/github-icon-vertical-align.user.js b/web/userscripts/github-icon-vertical-align.user.js
new file mode 100644
index 0000000..eb24152
--- /dev/null
+++ b/web/userscripts/github-icon-vertical-align.user.js
@@ -0,0 +1,17 @@
+// ==UserScript==
+// @name     GitHub icon vertical alignment fix
+// @version  2
+// @grant    GM_addStyle
+// @match    https://github.com/*
+// @match    https://gist.github.com/*
+// @run-at   document-start
+// ==/UserScript==
+
+(() => {
+  'use strict';
+  GM_addStyle(`
+    .btn-sm .octicon {
+      vertical-align: middle;
+    }
+  `);
+})();
diff --git a/web/userscripts/github-line-height.user.js b/web/userscripts/github-line-height.user.js
new file mode 100644
index 0000000..70b1aca
--- /dev/null
+++ b/web/userscripts/github-line-height.user.js
@@ -0,0 +1,19 @@
+// ==UserScript==
+// @name     GitHub line-height
+// @version  2
+// @grant    GM_addStyle
+// @match    https://github.com/*
+// @match    https://gist.github.com/*
+// @run-at   document-start
+// ==/UserScript==
+
+(() => {
+  'use strict';
+  const LINE_HEIGHT = '1.2';
+  GM_addStyle(`
+    .blob-num, .blob-code, .markdown-body .highlight pre, .markdown-body pre,
+    .cm-s-github-light .CodeMirror-lines, textarea.file-editor-textarea {
+      line-height: ${LINE_HEIGHT};
+    }
+  `);
+})();
diff --git a/web/userscripts/github-tab-size.user.js b/web/userscripts/github-tab-size.user.js
new file mode 100644
index 0000000..1dd581b
--- /dev/null
+++ b/web/userscripts/github-tab-size.user.js
@@ -0,0 +1,19 @@
+// ==UserScript==
+// @name     GitHub tab size 4
+// @version  2
+// @grant    GM_addStyle
+// @match    https://github.com/*
+// @match    https://gist.github.com/*
+// @run-at   document-start
+// ==/UserScript==
+
+(() => {
+  'use strict';
+  const TAB_SIZE = '4';
+  GM_addStyle(`
+    * {
+      -moz-tab-size: ${TAB_SIZE} !important;
+      tab-size: ${TAB_SIZE} !important;
+    }
+  `);
+})();
diff --git a/web/userscripts/steamcommunity-com-linkfilter.user.js b/web/userscripts/steamcommunity-com-linkfilter.user.js
new file mode 100644
index 0000000..324e011
--- /dev/null
+++ b/web/userscripts/steamcommunity-com-linkfilter.user.js
@@ -0,0 +1,16 @@
+// ==UserScript==
+// @name     steamcommunity.com linkfilter disabler
+// @version  1
+// @grant    none
+// @run-at   document-start
+// @match    https://steamcommunity.com/linkfilter/*
+// ==/UserScript==
+
+(() => {
+  'use strict';
+  let searchParams = new URLSearchParams(window.location.search);
+  let url = searchParams.get('url');
+  if (url) {
+    window.location.replace(url);
+  }
+})();
diff --git a/web/userscripts/twitter-s-param-remover.user.js b/web/userscripts/twitter-s-param-remover.user.js
new file mode 100644
index 0000000..42fb6bd
--- /dev/null
+++ b/web/userscripts/twitter-s-param-remover.user.js
@@ -0,0 +1,17 @@
+// ==UserScript==
+// @name     twitter ?s=20 remover
+// @version  1
+// @grant    none
+// @match    https://twitter.com/*
+// @run-at   document-start
+// ==/UserScript==
+
+(() => {
+  'use strict';
+  let searchParams = new URLSearchParams(window.location.search);
+  let strangeValue = searchParams.get('s');
+  if (/[0-9]+/.test(strangeValue)) {
+    searchParams.delete('s');
+    window.location.search = searchParams.toString();
+  }
+})();
diff --git a/web/userscripts/youtube-screenshot.user.js b/web/userscripts/youtube-screenshot.user.js
new file mode 100644
index 0000000..e2c2f29
--- /dev/null
+++ b/web/userscripts/youtube-screenshot.user.js
@@ -0,0 +1,30 @@
+// ==UserScript==
+// @name     YouTube screenshotter
+// @version  2
+// @grant    GM_addElement
+// @match    https://www.youtube.com/*
+// @run-at   document-end
+// ==/UserScript==
+
+(() => {
+  'use strict';
+
+  function main() {
+    window.__userscript__takeScreenshot = function (video, imageType = 'image/png') {
+      if (!(video instanceof HTMLVideoElement)) {
+        throw new Error('Assertion failed: video instanceof HTMLVideoElement');
+      }
+
+      let canvas = document.createElement('canvas');
+      canvas.width = video.videoWidth;
+      canvas.height = video.videoHeight;
+      let ctx = canvas.getContext('2d');
+      ctx.drawImage(video, 0, 0, video.videoWidth, video.videoHeight);
+      window.open(canvas.toDataURL(imageType), '_blank');
+    };
+  }
+
+  GM_addElement('script', {
+    textContent: `(${main.toString()})();`,
+  });
+})();