diff --git a/php/servers/servers-rooms.php b/php/servers/servers-rooms.php
index 607738c..8e498c6 100644
--- a/php/servers/servers-rooms.php
+++ b/php/servers/servers-rooms.php
@@ -417,7 +417,7 @@
 		public function add_tags(array $tags) {
 			$new_string_tags = [];
 			foreach ($tags as $tag) {
-				if (strlen($tag) == 0) continue;
+				if (strlen(trim($tag)) == 0) continue;
 				$this->string_tags[] = $tag;
 				if ($this->parse_language_tag($tag)) continue;
 				$new_string_tags[] = $tag;