diff --git a/web-src/js/common.js b/web-src/js/common.js
index 380e2d80..c7ed31c7 100644
--- a/web-src/js/common.js
+++ b/web-src/js/common.js
@@ -319,7 +319,7 @@ export function getWebsocketUrl(relativePath) {
 
     var dir = getUrlDir();
     if (dir) {
-        hostUrl += '/' + dir;
+        hostUrl += dir;
     }
 
     if (isEmptyString(relativePath)) {