installed plugin W3 Total Cache version 2.3.2

wp-content/plugins/w3-total-cache/Mobile_UserAgent.php

@@ -0,0 +1,37 @@
+<?php
+/**
+ * File: Mobile_UserAgent.php
+ *
+ * W3TC Mobile detection.
+ *
+ * @package W3TC
+ * @subpackage QA
+ */
+
+namespace W3TC;
+
+/**
+ * Class Mobile_UserAgent
+ */
+class Mobile_UserAgent extends Mobile_Base {
+	/**
+	 * PHP5-style constructor
+	 */
+	public function __construct() {
+		parent::__construct( 'mobile.rgroups', 'agents' );
+	}
+
+	/**
+	 * Group verifier.
+	 *
+	 * @param string $group_compare_value Group comparison value.
+	 * @return int|false
+	 */
+	public function group_verifier( $group_compare_value ) {
+		return preg_match(
+			'~' . $group_compare_value . '~i',
+			isset( $_SERVER['HTTP_USER_AGENT'] ) ?
+				htmlspecialchars( $_SERVER['HTTP_USER_AGENT'] ) : '' // phpcs:ignore
+		);
+	}
+}