diff --git a/packages/ui-default/components/editor/index.js b/packages/ui-default/components/editor/index.js
index 9404294d4..3ec3cc9aa 100644
--- a/packages/ui-default/components/editor/index.js
+++ b/packages/ui-default/components/editor/index.js
@@ -119,7 +119,7 @@ export default class Editor extends DOMAttachedObject {
 
   value(val) {
     this.ensureValid();
-    if (val) return this.editor.setValue(val);
+    if (typeof val === 'string') return this.editor.setValue(val);
     return this.editor.getValue();
   }
 
diff --git a/packages/ui-default/components/tab/Tab.js b/packages/ui-default/components/tab/Tab.js
index d73c5e9fb..fc134dd1b 100644
--- a/packages/ui-default/components/tab/Tab.js
+++ b/packages/ui-default/components/tab/Tab.js
@@ -13,7 +13,7 @@ export default class Tab extends DOMAttachedObject {
   }
 
   static initEventListeners() {
-    $(document).on('click', '.section__tab-header-item', (ev) => {
+    $(document).on('click', '[data-tab-index]', (ev) => {
       const targetIndex = $(ev.currentTarget).attr('data-tab-index');
       const $container = $(ev.currentTarget).closest('.section__tab-container');
       const tabInstance = Tab.get($container);
@@ -61,19 +61,21 @@ export default class Tab extends DOMAttachedObject {
 
     // 2. Animate transition
     $currentTab
-      .transition({
-        opacity: 0,
-      }, {
-        duration: TAB_TRANSITION_DURATION,
-        easing: 'linear',
-      });
+      .transition(
+        { opacity: 0 },
+        {
+          duration: TAB_TRANSITION_DURATION,
+          easing: 'linear',
+        }
+      );
     $newTab
-      .transition({
-        opacity: 1,
-      }, {
-        duration: TAB_TRANSITION_DURATION,
-        easing: 'linear',
-      });
+      .transition(
+        { opacity: 1 },
+        {
+          duration: TAB_TRANSITION_DURATION,
+          easing: 'linear',
+        }
+      );
     await this.$content
       .transition({
         x: animateParameter.to,
@@ -97,9 +99,7 @@ export default class Tab extends DOMAttachedObject {
   }
 
   attach() {
-    if (this.attached) {
-      return false;
-    }
+    if (this.attached) return false;
 
     const $container = this.$dom
       .closest('.section__tab-container');
diff --git a/packages/ui-default/package.json b/packages/ui-default/package.json
index d64481778..68d188391 100644
--- a/packages/ui-default/package.json
+++ b/packages/ui-default/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@hydrooj/ui-default",
-  "version": "4.6.31",
+  "version": "4.6.32",
   "author": "undefined <i@undefined.moe>",
   "license": "AGPL-3.0",
   "main": "hydro.js",
diff --git a/packages/ui-default/pages/problem_edit.page.js b/packages/ui-default/pages/problem_edit.page.js
index 13d247daf..0e3268e1f 100644
--- a/packages/ui-default/pages/problem_edit.page.js
+++ b/packages/ui-default/pages/problem_edit.page.js
@@ -177,14 +177,17 @@ export default new NamedPage(['problem_create', 'problem_edit'], (pagename) => {
     });
   }, 50);
 
-  const $main = $('textarea[data-markdown-upload]');
-  let content = $main.val();
+  const $main = $('textarea[data-editor]');
+  const $field = $('textarea[data-markdown-upload]');
+  let content = $field.val();
   let isObject = false;
+  let activeTab = $('[data-lang]').first().attr('data-lang');
   try {
     content = JSON.parse(content);
     isObject = !(content instanceof Array);
     if (!isObject) content = JSON.stringify(content);
   } catch (e) { }
+  if (!isObject) content = { [activeTab]: content };
   const upload = {
     accept: 'image/*,.mp3, .wav, .zip',
     url: './files',
@@ -229,30 +232,35 @@ export default new NamedPage(['problem_create', 'problem_edit'], (pagename) => {
     },
     validate: () => (pagename === 'problem_create' ? i18n('Cannot upload file before problem is created.') : true),
   };
-  $('textarea[data-content]').each(function () {
-    const $dom = $(this);
-    let i = $dom.attr('data-content');
+  function getContent(lang) {
     let c = '';
-    if (isObject) {
-      if (content[i]) c = content[i];
-      else {
-        const list = Object.keys(content).filter((l) => l.startsWith(i));
-        if (list.length) c = content[list[0]];
-        [i] = list;
-      }
-    } else c = content;
-    if (typeof c !== 'string') c = JSON.stringify(c);
-    $dom.val(c);
-    function onChange(val) {
-      if (!isObject) {
-        content = { [i]: val };
-        isObject = true;
-      }
-      const empty = /^\s*$/g.test(val);
-      if (empty) delete content[i];
-      else content[i] = val;
-      $main.val(JSON.stringify(content));
+    if (content[lang]) c = content[lang];
+    else {
+      const list = Object.keys(content).filter((l) => l.startsWith(lang));
+      if (list.length) c = content[list[0]];
     }
-    Editor.getOrConstruct($dom, { upload, onChange });
+    if (typeof c !== 'string') c = JSON.stringify(c);
+    return c;
+  }
+  $main.val(getContent(activeTab));
+  function onChange(val) {
+    console.log('onChange', activeTab, val);
+    try {
+      val = JSON.parse(val);
+      if (!(val instanceof Array)) val = JSON.stringify(val);
+    } catch { }
+    const empty = /^\s*$/g.test(val);
+    if (empty) delete content[activeTab];
+    else content[activeTab] = val;
+    console.log(content);
+    if (!Object.keys(content).length) $field.text('');
+    else $field.text(JSON.stringify(content));
+  }
+  const editor = Editor.getOrConstruct($main, { upload, onChange });
+  $('[data-lang]').on('click', (ev) => {
+    const lang = $(ev.currentTarget).attr('data-lang');
+    activeTab = lang;
+    const val = getContent(lang);
+    editor.value(val);
   });
 });
diff --git a/packages/ui-default/templates/problem_edit.html b/packages/ui-default/templates/problem_edit.html
index 2ef188ff8..c93c38e1a 100644
--- a/packages/ui-default/templates/problem_edit.html
+++ b/packages/ui-default/templates/problem_edit.html
@@ -38,29 +38,18 @@
                value:pdoc['tag']|default([])|join(', ')
              }) }}
           <div class="section__tab-container nojs--hide">
-            <ul class="section__tabs immersive">
-              <li class="section__tab-item">
-                <h1 class="section__tab-title">{{ _('__langname') }}</h1>
-                <div class="section__tab-main">
-                  <div class="section__body">
-                    <textarea data-content="{{ _('__id') }}" class="textbox" style="height: 500px"></textarea>
-                  </div>
-                </div>
-              </li>
+          <div class="section__tab-header-wrapper">
+            <ul class="section__tab-header">
+              <li class="section__tab-header-item" data-lang="{{ _('__id') }}">{{ _('__langname') }}</li>
               {% for k, v in model.setting.SETTINGS_BY_KEY['viewLang'].range %}
                 {% if k != handler.user.viewLang %}
-                  <li class="section__tab-item">
-                    <h1 class="section__tab-title">{{ v }}</h1>
-                    <div class="section__tab-main">
-                      <div class="section__body">
-                        <textarea data-content="{{ k }}" class="textbox" style="height: 500px"></textarea>
-                      </div>
-                    </div>
-                  </li>
-                {% endif %}
-              {% endfor %}
+              <li class="section__tab-header-item" data-lang="{{ k }}">{{ v }}</li>
+              {% endif %}
+            {% endfor %}
             </ul>
+            </div>
           </div>
+          <div><textarea data-editor class="nojs--hide"></textarea></div>
           <textarea name="content" class="textbox hasjs--hide" data-markdown-upload style="height: 500px">{% if pdoc %}{{ pdoc['content']|toString }}{% else %}{% include 'partials/problem_default.md' %}{% endif %}</textarea>
           <div class="row"><div class="columns">
             <input type="hidden" name="csrfToken" value="{{ handler.csrfToken }}">