diff --git a/LayoutTests/ChangeLog b/LayoutTests/ChangeLog
index 60c6160..1e93c15 100644
--- a/LayoutTests/ChangeLog
+++ b/LayoutTests/ChangeLog
@@ -1,3 +1,21 @@
+2019-10-15  Wenson Hsieh  <wenson_hsieh@apple.com>
+
+        editing/async-clipboard/clipboard-item-basic.html is a flaky failure on macOS and iOS
+        https://bugs.webkit.org/show_bug.cgi?id=203015
+
+        Reviewed by Tim Horton.
+
+        This test, for the most part, finishes and dumps its final output before a couple of (intentionally) rejected
+        promises finish and log their uncaught rejections to the console. In the case where we lose this race and the
+        console messages happen earlier, we end up with a text diff failure.
+
+        Avoid this issue by making sure that we catch these promise rejections.
+
+        * editing/async-clipboard/clipboard-item-basic.html:
+
+        Also give this test a tiny bit more variety, by making one of the promises reject immediately, while the other
+        still waits for a short delay (50 ms).
+
 2019-10-15  Carlos Alberto Lopez Perez  <clopez@igalia.com>
 
         Import apng testcases from WPT.
diff --git a/LayoutTests/editing/async-clipboard/clipboard-item-basic.html b/LayoutTests/editing/async-clipboard/clipboard-item-basic.html
index 1a3b62d..de6cdf4 100644
--- a/LayoutTests/editing/async-clipboard/clipboard-item-basic.html
+++ b/LayoutTests/editing/async-clipboard/clipboard-item-basic.html
@@ -143,8 +143,10 @@
             await (async function() {
                 item = tryToCreateClipboardItem({
                     "text/plain" : Promise.resolve("謝謝"),
-                    "text/html" : new Promise((_, reject) => setTimeout(() => reject(imageBlob()), 50)),
-                    "image/png" : new Promise((_, reject) => setTimeout(() => reject(imageBlob()), 50)),
+                    "text/html" : new Promise((_, reject) => {
+                        setTimeout(reject, 50);
+                    }).catch(() => { }),
+                    "image/png" : Promise.reject(imageBlob()).catch(() => { }),
                     "🤔🤔🤔" : Promise.resolve("מקור השם עברית"),
                     "מקור השם עברית" : Promise.resolve("🤔🤔🤔")
                 });