diff --git a/src/bundle/Resources/encore/ez.webpack.custom.config.js b/src/bundle/Resources/encore/ez.webpack.custom.config.js
index c866bdbb..21424e50 100644
--- a/src/bundle/Resources/encore/ez.webpack.custom.config.js
+++ b/src/bundle/Resources/encore/ez.webpack.custom.config.js
@@ -1,71 +1,80 @@
-const Encore = require('@symfony/webpack-encore');
 const path = require('path');
 const { styles } = require(path.resolve('./public/bundles/ibexaadminuiassets/vendors/@ckeditor/ckeditor5-dev-utils'));
 const ibexaConfigManager = require(path.resolve('./ibexa.webpack.config.manager.js'));
 const configManagers = require(path.resolve('./var/encore/ibexa.richtext.config.manager.js'));
 
-Encore.reset();
-Encore.setOutputPath('public/assets/richtext/build').setPublicPath('/assets/richtext/build').enableSassLoader().disableSingleRuntimeChunk();
+const getCustomConfig = (Encore) => {
+    Encore.reset();
+    Encore.setOutputPath('public/assets/richtext/build').setPublicPath('/assets/richtext/build').enableSassLoader().disableSingleRuntimeChunk();
 
-Encore.addEntry('ibexa-richtext-onlineeditor-js', [path.resolve(__dirname, '../public/js/CKEditor/core/base-ckeditor.js')]).addStyleEntry(
-    'ibexa-richtext-onlineeditor-css',
-    [path.resolve(__dirname, '../public/scss/ckeditor.scss')],
-);
+    Encore.addEntry('ibexa-richtext-onlineeditor-js', [path.resolve(__dirname, '../public/js/CKEditor/core/base-ckeditor.js')]).addStyleEntry(
+        'ibexa-richtext-onlineeditor-css',
+        [path.resolve(__dirname, '../public/scss/ckeditor.scss')],
+    );
 
-Encore.addAliases({
-    '@ckeditor': path.resolve('./public/bundles/ibexaadminuiassets/vendors/@ckeditor'),
-    '@fieldtype-richtext': path.resolve('./vendor/ibexa/fieldtype-richtext'),
-    '@ibexa-admin-ui': path.resolve('./vendor/ibexa/admin-ui'),
-});
+    Encore.addAliases({
+        '@ckeditor': path.resolve('./public/bundles/ibexaadminuiassets/vendors/@ckeditor'),
+        '@fieldtype-richtext': path.resolve('./vendor/ibexa/fieldtype-richtext'),
+        '@ibexa-admin-ui': path.resolve('./vendor/ibexa/admin-ui'),
+    });
 
-const customConfig = Encore.getWebpackConfig();
+    const customConfig = Encore.getWebpackConfig();
 
-customConfig.name = 'richtext';
+    customConfig.name = 'richtext';
 
-customConfig.module.rules[4].oneOf[1].use[1].options.url = false;
-customConfig.module.rules[1].oneOf[1].use[1].options.url = false;
+    customConfig.module.rules[4].oneOf[1].use[1].options.url = false;
+    customConfig.module.rules[1].oneOf[1].use[1].options.url = false;
 
-customConfig.module.rules.push({
-    test: /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
-    use: ['raw-loader'],
-});
+    customConfig.module.rules.push({
+        test: /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
+        use: ['raw-loader'],
+    });
 
-customConfig.module.rules.push({
-    test: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css$/,
-    use: [
-        {
-            loader: 'style-loader',
-            options: {
-                injectType: 'singletonStyleTag',
-                attributes: {
-                    'data-cke': true,
+    customConfig.module.rules.push({
+        test: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css$/,
+        use: [
+            {
+                loader: 'style-loader',
+                options: {
+                    injectType: 'singletonStyleTag',
+                    attributes: {
+                        'data-cke': true,
+                    },
                 },
             },
-        },
-        'css-loader',
-        {
-            loader: 'postcss-loader',
-            options: {
-                postcssOptions: styles.getPostCssConfig({
-                    themeImporter: {
-                        themePath: require.resolve(
-                            path.resolve('./public/bundles/ibexaadminuiassets/vendors/@ckeditor/ckeditor5-theme-lark'),
-                        ),
-                    },
-                    minify: true,
-                }),
+            'css-loader',
+            {
+                loader: 'postcss-loader',
+                options: {
+                    postcssOptions: styles.getPostCssConfig({
+                        themeImporter: {
+                            themePath: require.resolve(
+                                path.resolve('./public/bundles/ibexaadminuiassets/vendors/@ckeditor/ckeditor5-theme-lark'),
+                            ),
+                        },
+                        minify: true,
+                    }),
+                },
             },
-        },
-    ],
-});
+        ],
+    });
+
+    customConfig.module.rules[1] = {};
+    customConfig.module.rules[2] = {};
+
+    configManagers.forEach((configManagerPath) => {
+        const configManager = require(path.resolve(configManagerPath));
 
-customConfig.module.rules[1] = {};
-customConfig.module.rules[2] = {};
+        configManager(customConfig, ibexaConfigManager);
+    });
 
-configManagers.forEach((configManagerPath) => {
-    const configManager = require(path.resolve(configManagerPath));
+    return customConfig;
+}
 
-    configManager(customConfig, ibexaConfigManager);
-});
+try {
+    const Encore = require('@symfony/webpack-encore');
 
-module.exports = customConfig;
+    module.exports = getCustomConfig(Encore);
+} catch {
+    module.exports = getCustomConfig;
+}