1 files changed, 19 insertions, 3 deletions
diff --git a/dom/webgpu/tests/cts/checkout/src/common/internal/logging/result.ts b/dom/webgpu/tests/cts/checkout/src/common/internal/logging/result.ts
index 3318e8c937..9968f3d359 100644
--- a/dom/webgpu/tests/cts/checkout/src/common/internal/logging/result.ts
+++ b/dom/webgpu/tests/cts/checkout/src/common/internal/logging/result.ts
@@ -14,8 +14,24 @@ export interface LiveTestCaseResult extends TestCaseResult {
   logs?: LogMessageWithStack[];
 }
 
+/**
+ * Raw data for a test log message.
+ *
+ * This form is sendable over a message channel, except `extra` may get mangled.
+ */
+export interface LogMessageRawData {
+  name: string;
+  message: string;
+  stackHiddenMessage: string | undefined;
+  stack: string | undefined;
+  extra: unknown;
+}
+
+/**
+ * Test case results in a form sendable over a message channel.
+ *
+ * Note `extra` may get mangled by postMessage.
+ */
 export interface TransferredTestCaseResult extends TestCaseResult {
-  // When transferred from a worker, a LogMessageWithStack turns into a generic Error
-  // (its prototype gets lost and replaced with Error).
-  logs?: Error[];
+  logs?: LogMessageRawData[];
 }