diff --git a/background/update-manager.js b/background/update-manager.js
index 1c975281..0796e4af 100644
--- a/background/update-manager.js
+++ b/background/update-manager.js
@@ -63,7 +63,7 @@ const updateMan = (() => {
     checkingAll = true;
     const port = observe && chrome.runtime.connect({name: 'updater'});
     const styles = (await API.styles.getAll())
-      .filter(style => style.updateUrl);
+      .filter(style => style.updateUrl && style.updatable !== false);
     if (port) port.postMessage({count: styles.length});
     log('');
     log(`${save ? 'Scheduled' : 'Manual'} update check for ${styles.length} styles`);
diff --git a/edit/settings.css b/edit/settings.css
index 32397434..d4da2290 100644
--- a/edit/settings.css
+++ b/edit/settings.css
@@ -23,10 +23,13 @@
 .style-settings input[type=radio] {
   margin-left: -.5em; /* compensate for label's 16px margin in edit.css */
 }
-.style-settings input[type=text],
-.style-settings input[type=number],
-.style-settings select,
-.style-settings textarea {
+.style-settings input:disabled ~ label {
+  opacity: .5;
+}
+.style-settings .rel {
+  position: relative;
+}
+.style-settings .w100 {
   display: block;
   width: 100%;
   margin-top: .25em;
diff --git a/edit/settings.html b/edit/settings.html
index 054beece..725a1ba8 100644
--- a/edit/settings.html
+++ b/edit/settings.html
@@ -1,8 +1,11 @@
 <div>
   <fieldset class="style-settings can-close-on-esc">
-    <label i18n-text="styleUpdateUrlLabel">
-      <input id="ss-update-url" type="text">
-    </label>
+    <div class="rel">
+      <input id="ss-updatable" type="checkbox">
+      <svg class="svg-icon checked"><use xlink:href="#svg-icon-checked"/></svg>
+      <label i18n-text="installUpdateFromLabel" for="ss-updatable"></label>
+      <input id="ss-update-url" type="url" class="w100" i18n-placeholder="styleUpdateUrlLabel">
+    </div>
     <div id="ss-scheme">
       <div i18n-text="installPreferSchemeLabel"></div>
       <label i18n-text-append="installPreferSchemeNone">
@@ -16,11 +19,11 @@
       </label>
     </div>
     <label i18n-text="styleIncludeLabel">
-      <textarea id="ss-inclusions" spellcheck="false"
+      <textarea id="ss-inclusions" spellcheck="false" class="w100"
                 placeholder="*://site1.com/*&#10;*://site2.com/*"></textarea>
     </label>
     <label i18n-text="styleExcludeLabel">
-      <textarea id="ss-exclusions" spellcheck="false"
+      <textarea id="ss-exclusions" spellcheck="false" class="w100"
                 placeholder="*://site1.com/*&#10;*://site2.com/*"></textarea>
     </label>
   </fieldset>
diff --git a/edit/settings.js b/edit/settings.js
index e1264f11..855bdb0a 100644
--- a/edit/settings.js
+++ b/edit/settings.js
@@ -1,26 +1,32 @@
-/* global $ $$ moveFocus setupLivePrefs */// dom.js
+/* global $ moveFocus setupLivePrefs */// dom.js
 /* global API */// msg.js
 /* global editor */
 /* global helpPopup */// util.js
 /* global t */// localization.js
-/* global debounce */// toolbox.js
+/* global debounce tryURL */// toolbox.js
 /* exported StyleSettings */
 'use strict';
 
 async function StyleSettings() {
   const AUTOSAVE_DELAY = 500; // same as config-dialog.js
   const SS_ID = 'styleSettings';
+  const PASS = val => val;
   await t.fetchTemplate('/edit/settings.html', SS_ID);
   const {style} = editor;
   const ui = t.template[SS_ID].cloneNode(true);
   const elAuto = $('#config\\.autosave', ui);
   const elSave = $('#ss-save', ui);
+  const elUpd = $('#ss-updatable', ui);
   const pendingSetters = new Map();
   const updaters = [
-    initInput('#ss-update-url', () => style.updateUrl || '',
-      val => API.styles.config(style.id, 'updateUrl', val)),
-    initRadio('ss-scheme', () => style.preferScheme || 'none',
-      val => API.styles.config(style.id, 'preferScheme', val)),
+    initCheckbox(elUpd, 'updatable', tryURL(style.updateUrl).href),
+    initInput('#ss-update-url', 'updateUrl', '', {
+      validate(el) {
+        elUpd.disabled = !el.value || !el.validity.valid;
+        return el.validity.valid;
+      },
+    }),
+    initRadio('ss-scheme', 'preferScheme', 'none'),
     initArea('inclusions'),
     initArea('exclusions'),
   ];
@@ -43,51 +49,67 @@ async function StyleSettings() {
   }
 
   function initArea(type) {
-    const selector = `#ss-${type}`;
-    const el = $(selector, ui);
-    el.oninput = () => {
-      const val = el.value;
-      el.rows = val.match(/^/gm).length + !val.endsWith('\n');
-    };
-    return initInput(selector,
-      () => {
-        const list = style[type] || [];
-        const text = list.join('\n');
-        el.rows = (list.length || 1) + 1;
-        return text;
+    return initInput(`#ss-${type}`, type, [], {
+      get: textToList,
+      set: list => list.join('\n'),
+      validate(el) {
+        const val = el.value;
+        el.rows = val.match(/^/gm).length + !val.endsWith('\n');
       },
-      val => API.styles.config(style.id, type, textToList(val))
-    );
+    });
   }
 
-  function initInput(selector, getter, setter) {
-    const el = $(selector, ui);
-    el.oninput = () => autosave(el, setter);
+  function initCheckbox(el, key, defVal) {
+    return initInput(el, key, Boolean(defVal), {dom: 'checked'});
+  }
+
+  function initInput(el, key, defVal, {
+    dom = 'value', // DOM property name
+    get = PASS, // transformer function(val) after getting DOM value
+    set = PASS, // transformer function(val) before setting DOM value
+    validate = PASS, // function(el) - return `false` to prevent saving
+  } = {}) {
+    if (typeof el === 'string') {
+      el = $(el, ui);
+    }
+    el.oninput = () => {
+      if (validate(el) !== false) {
+        autosave(el, {dom, get, key});
+      }
+    };
     return () => {
-      const val = getter();
+      let val = style[key];
+      val = set(val != null ? val : defVal);
       // Skipping if unchanged to preserve the Undo history of the input
-      if (el.value !== val) el.value = val;
+      if (el[dom] !== val) el[dom] = val;
+      validate(el);
     };
   }
 
-  function initRadio(name, getter, setter) {
-    for (const el of $$(`[name="${name}"]`, ui)) {
-      el.onchange = () => {
-        if (el.checked) autosave(el, setter);
-      };
-    }
+  function initRadio(name, key, defVal) {
+    $(`#${name}`, ui).oninput = e => {
+      if (e.target.checked) {
+        autosave(e.target, {key});
+      }
+    };
     return () => {
-      $(`[name="${name}"][value="${getter()}"]`, ui).checked = true;
+      const val = style[key] || defVal;
+      const el = $(`[name="${name}"][value="${val}"]`, ui);
+      el.checked = true;
     };
   }
 
   function save() {
-    pendingSetters.forEach((fn, el) => fn(el.value));
+    pendingSetters.forEach(saveValue);
     pendingSetters.clear();
     helpPopup.div.classList.remove('dirty');
     elSave.disabled = true;
   }
 
+  function saveValue({dom = 'value', get = PASS, key}, el) {
+    return API.styles.config(style.id, key, get(el[dom]));
+  }
+
   function textToList(text) {
     return text.split(/\n/).map(s => s.trim()).filter(Boolean);
   }