Fix the default value for the custom CSS field

See https://www.woltlab.com/community/thread/302018-individuelles-css-und-scss-erg%C3%A4nzend-f%C3%BCr-dunkles-farbschema/

wcfsetup/install/files/acp/update_com.woltlab.wcf_6.0.1.php

@@ -0,0 +1,29 @@
+<?php
+
+/**
+ * Fixes the style variable value of `individualScssDarkMode`.
+ *
+ * @author Alexander Ebert
+ * @copyright 2001-2023 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ */
+
+use wcf\system\WCF;
+
+// Fix the default value for style variables.
+$sql = "UPDATE wcf1_style_variable
+ SET defaultValueDarkMode = ?
+ WHERE variableName = ?";
+$statement = WCF::getDB()->prepare($sql);
+$statement->execute([null, 'individualScssDarkMode']);
+
+// Fixes any bad values stored for existing styles.
+$sql = "UPDATE wcf1_style_variable_value
+ SET variableValueDarkMode = ?
+ WHERE variableID = (
+ SELECT variableID
+ FROM wcf1_style_variable
+ WHERE variableName = ?
+ )";
+$statement = WCF::getDB()->prepare($sql);
+$statement->execute([null, 'individualScssDarkMode']);