diff --git a/copyparty/web/util.js b/copyparty/web/util.js
index 0f2c3ca8..388206a1 100644
--- a/copyparty/web/util.js
+++ b/copyparty/web/util.js
@@ -85,15 +85,18 @@ catch (ex) {
 }
 var crashed = false, ignexd = {};
 function vis_exh(msg, url, lineNo, columnNo, error) {
-    if ((msg + '').indexOf('ResizeObserver') !== -1)
+    if ((msg + '').indexOf('ResizeObserver') + 1)
         return;  // chrome issue 809574 (benign, from <video>)
 
-    if ((msg + '').indexOf('l2d.js') !== -1)
+    if ((msg + '').indexOf('l2d.js') + 1)
         return;  // `t` undefined in tapEvent -> hitTestSimpleCustom
 
     if (!/\.js($|\?)/.exec('' + url))
         return;  // chrome debugger
 
+    if ((url + '').indexOf(' > eval') + 1)
+        return;  // md timer
+
     var ekey = url + '\n' + lineNo + '\n' + msg;
     if (ignexd[ekey] || crashed)
         return;