diff --git a/testing/web-platform/tests/2dcontext/context-attributes/getContextAttributes.html b/testing/web-platform/tests/2dcontext/context-attributes/getContextAttributes.html
index 15b61933a1d62..cfb563e98be5b 100644
--- a/testing/web-platform/tests/2dcontext/context-attributes/getContextAttributes.html
+++ b/testing/web-platform/tests/2dcontext/context-attributes/getContextAttributes.html
@@ -59,6 +59,9 @@
 alpha
 :
 true
+desynchronized
+:
+false
 }
 }
 {
@@ -115,6 +118,33 @@
 false
 }
 }
+{
+testDescription
+:
+"
+Test
+context
+creation
+attributes
+desynchronized
+:
+false
+"
+canvasContextAttributes
+:
+{
+desynchronized
+:
+false
+}
+expectedContextAttributes
+:
+{
+desynchronized
+:
+false
+}
+}
 ]
 ;
 function
@@ -168,6 +198,19 @@
 (
 )
 ;
+if
+(
+testScenario
+.
+expectedContextAttributes
+.
+alpha
+!
+=
+=
+undefined
+)
+{
 assert_equals
 (
 contextAttributes
@@ -181,6 +224,33 @@
 )
 ;
 }
+if
+(
+testScenario
+.
+expectedContextAttributes
+.
+desynchronized
+!
+=
+=
+undefined
+)
+{
+assert_equals
+(
+contextAttributes
+.
+desynchronized
+testScenario
+.
+expectedContextAttributes
+.
+desynchronized
+)
+;
+}
+}
 testScenario
 .
 testDescription