diff --git a/testing/web-platform/tests/preload/onerror-event.html b/testing/web-platform/tests/preload/onerror-event.html
index 94c8dc772dee..fb29956b89a0 100644
--- a/testing/web-platform/tests/preload/onerror-event.html
+++ b/testing/web-platform/tests/preload/onerror-event.html
@@ -1,6 +1,7 @@
 <!DOCTYPE html>
 <html>
 <title>Makes sure that preloaded resources trigger the onerror event</title>
+<meta name="timeout" content="long">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script src="/preload/resources/preload_helper.js"></script>
diff --git a/testing/web-platform/tests/preload/onload-event.html b/testing/web-platform/tests/preload/onload-event.html
index 8825ffaaa520..2e1e8d390071 100644
--- a/testing/web-platform/tests/preload/onload-event.html
+++ b/testing/web-platform/tests/preload/onload-event.html
@@ -1,5 +1,6 @@
 <!DOCTYPE html>
 <title>Makes sure that preloaded resources trigger the onload event</title>
+<meta name="timeout" content="long">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script src="/preload/resources/preload_helper.js"></script>
