diff --git a/code/html/custom.js b/code/html/custom.js
index 9a4150e0..b77f1655 100644
--- a/code/html/custom.js
+++ b/code/html/custom.js
@@ -1358,6 +1358,8 @@ $(function() {
     $(document).on("change", "input", hasChanged);
     $(document).on("change", "select", hasChanged);
 
+    // don't autoconnect when opening from filesystem
+    if (window.location.protocol === "file:") { return; }
     connect();
 
 });