diff --git a/Classes/Hooks/Backend/Template/DocumentTemplate.php b/Classes/Hooks/Backend/Template/DocumentTemplate.php
index 9ffabe5..fe4fe8c 100644
--- a/Classes/Hooks/Backend/Template/DocumentTemplate.php
+++ b/Classes/Hooks/Backend/Template/DocumentTemplate.php
@@ -4,6 +4,7 @@
 namespace Wazum\PagetreeResizable\Hooks\Backend\Template;
 
 use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Core\Utility\VersionNumberUtility;
 
 /**
@@ -14,6 +15,62 @@
  */
 class DocumentTemplate
 {
+    /**
+     * Executed when makeInstance is used (= in the link handler)
+     * Used in TYPO3 v10, but can replace all other parts as well.
+     */
+    public function __construct()
+    {
+        if (TYPO3_MODE === 'BE') {
+            $pageRenderer = GeneralUtility::makeInstance(PageRenderer::class);
+            if ($width = $this->getUserElementBrowserTreeWidth()) {
+                $pageRenderer->addCssInlineBlock('wazum/pagetree-resizable', '
+                .element-browser-main .element-browser-main-sidebar {
+                    width: ' . $width . 'px;
+                }
+            ');
+            }
+            $this->includeRequiredResources();
+        }
+
+    }
+
+    /**
+     * Used within the main backend module to add JS + CSS.
+     */
+    public function mainBackendModule()
+    {
+        $pageRenderer = GeneralUtility::makeInstance(PageRenderer::class);
+        if ($width = $this->getUserPageTreeWidth()) {
+            $pageRenderer->addCssInlineBlock('wazum/pagetree-resizable', '
+            .scaffold-content-navigation-expanded .scaffold-content-navigation {
+                width: ' . $width . 'px;
+            }
+            .scaffold-content-navigation-expanded .scaffold-content-module {
+                left: ' . $width . 'px;
+            }
+        ');
+        }
+        $this->includeRequiredResources();
+    }
+
+    /**
+     * Load CSS & JS resources into PageRenderer
+     */
+    protected function includeRequiredResources()
+    {
+        $pageRenderer = GeneralUtility::makeInstance(PageRenderer::class);
+        list($version) = explode('.', VersionNumberUtility::getCurrentTypo3Version());
+        $pageRenderer->addCssFile('EXT:pagetree_resizable/Resources/Public/Stylesheet/PagetreeResizable.css');
+        if ((int)$version === 8) {
+            $pageRenderer->loadRequireJsModule('TYPO3/CMS/PagetreeResizable/PagetreeResizable8');
+        } else {
+            // TYPO3 9, 10
+            $pageRenderer->loadRequireJsModule('TYPO3/CMS/PagetreeResizable/PagetreeResizable9');
+        }
+
+    }
+
     /**
      * @param array $parameters
      * @param \TYPO3\CMS\Backend\Template\DocumentTemplate $parent
diff --git a/Resources/Public/JavaScript/PagetreeResizable.js b/Resources/Public/JavaScript/PagetreeResizable.js
index eb47400..f1d8327 100644
--- a/Resources/Public/JavaScript/PagetreeResizable.js
+++ b/Resources/Public/JavaScript/PagetreeResizable.js
@@ -37,10 +37,10 @@ define([
                 isPageModule = true;
             }
             // Link browser
-            else if ($('.element-browser .element-browser-main .element-browser-main-sidebar').length) {
-                container = $('.element-browser .element-browser-main .element-browser-main-sidebar');
+            else if ($('.element-browser-main .element-browser-main-sidebar').length) {
+                container = $('.element-browser-main .element-browser-main-sidebar');
                 styles = function (width) {
-                    return '<style>.element-browser .element-browser-main .element-browser-main-sidebar{width:' + width + 'px}</style>';
+                    return '<style>.element-browser-main .element-browser-main-sidebar{width:' + width + 'px}</style>';
                 };
                 contentWidth = function () {
                     if ($('.element-browser-main-sidebar .element-browser-body ul.list-tree-root').length) {
@@ -54,6 +54,7 @@ define([
                     handles: 'e, w',
                     minWidth: 200,
                     create: function () {
+                        console.debug(container);
                         container.find('.ui-resizable-e').dblclick(function (e) {
                             var width = contentWidth();
                             if (width !== false) {
diff --git a/Resources/Public/Stylesheet/PagetreeResizable.css b/Resources/Public/Stylesheet/PagetreeResizable.css
index efacafc..645bbb5 100644
--- a/Resources/Public/Stylesheet/PagetreeResizable.css
+++ b/Resources/Public/Stylesheet/PagetreeResizable.css
@@ -37,4 +37,4 @@
     .element-browser .element-browser-main .element-browser-main-sidebar {
         width: auto !important;
     }
-}
+}
\ No newline at end of file
diff --git a/composer.json b/composer.json
index b2227ca..7de0735 100644
--- a/composer.json
+++ b/composer.json
@@ -4,7 +4,7 @@
   "description": "Make the backend page tree horizontally resizable",
   "require": {
     "php": ">=7.0.0",
-    "typo3/cms-core": "^8.7 || ^9.5 || ^10.2"
+    "typo3/cms-core": "^8.7 || ^9.5 || ^10.4"
   },
   "type": "typo3-cms-extension",
   "version": "1.2.1",
diff --git a/ext_emconf.php b/ext_emconf.php
index 1ea9d63..e693838 100644
--- a/ext_emconf.php
+++ b/ext_emconf.php
@@ -12,7 +12,7 @@
     'version' => '1.2.1',
     'constraints' => [
         'depends' => [
-            'typo3' => '8.7.0-10.2.99',
+            'typo3' => '8.7.0-10.4.99',
         ]
     ]
 ];
diff --git a/ext_localconf.php b/ext_localconf.php
index a39a22c..b743789 100644
--- a/ext_localconf.php
+++ b/ext_localconf.php
@@ -5,4 +5,10 @@
 if (TYPO3_MODE === 'BE') {
     $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['typo3/template.php']['preHeaderRenderHook']['wazum/pagetree-resizeable'] =
         \Wazum\PagetreeResizable\Hooks\Backend\Template\DocumentTemplate::class . '->preHeaderRenderHook';
+
+
+    // Necessary for TYPO3 v10
+    $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['LinkBrowser']['hooks']['wazum/pagetree-resizeable']['handler'] = \Wazum\PagetreeResizable\Hooks\Backend\Template\DocumentTemplate::class;
+    $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['typo3/backend.php']['renderPreProcess']['wazum/pagetree-resizeable'] =
+        \Wazum\PagetreeResizable\Hooks\Backend\Template\DocumentTemplate::class . '->mainBackendModule';
 }