diff --git a/src/messenger/webim/libs/common/misc.php b/src/messenger/webim/libs/common/misc.php
index cb1e2248..d26aa0c1 100644
--- a/src/messenger/webim/libs/common/misc.php
+++ b/src/messenger/webim/libs/common/misc.php
@@ -53,6 +53,56 @@ function div($a, $b)
 	return ($a - ($a % $b)) / $b;
 }
 
-
+/**
+ * Flatten array recursively.
+ *
+ * For example if input array is:
+ * <code>
+ *   $input = array(
+ *     'first' => 1,
+ *     'second' => array(
+ *       'f' => 'value',
+ *       's' => null,
+ *       't' => array(
+ *         'one', 'two', 'three'
+ *       ),
+ *       'f' => 4
+ *     ),
+ *     'third' => false,
+ *   );
+ * </code>
+ * the output array will be:
+ * <code>
+ *   $output = array(
+ *     'first' => 1,
+ *     'second.f' => 'value',
+ *     'second.s' => null,
+ *     'second.t.0' => 'one',
+ *     'second.t.1' => 'two',
+ *     'second.t.2' => 'three'
+ *     'second.f' => 4,
+ *     'third' => false
+ *   );
+ * </code>
+ *
+ * @param array $arr Array to flatten
+ * @return array
+ */
+function array_flatten_recursive($arr) {
+	$result = array();
+	foreach($arr as $key => $value) {
+		if (is_array($value)) {
+			// Flatten nested arrays
+			$value = array_flatten_recursive($value);
+			foreach($value as $inner_key => $inner_value) {
+				$result[$key.".".$inner_key] = $inner_value;
+			}
+		} else {
+			// Leave scalar values 'as is'
+			$result[$key] = $value;
+		}
+	}
+	return $result;
+}
 
 ?>
\ No newline at end of file