diff --git a/test/Notifier-test.ts b/test/Notifier-test.ts
index 498151fa1f0..3dbeae49012 100644
--- a/test/Notifier-test.ts
+++ b/test/Notifier-test.ts
@@ -81,6 +81,7 @@ describe("Notifier", () => {
             decryptEventIfNeeded: jest.fn(),
             getRoom: jest.fn(),
             getPushActionsForEvent: jest.fn(),
+            supportsExperimentalThreads: jest.fn().mockReturnValue(false),
         });
 
         mockClient.pushRules = {
diff --git a/test/components/structures/ThreadView-test.tsx b/test/components/structures/ThreadView-test.tsx
index 2893958a8f0..9fe83719955 100644
--- a/test/components/structures/ThreadView-test.tsx
+++ b/test/components/structures/ThreadView-test.tsx
@@ -108,6 +108,7 @@ describe("ThreadView", () => {
         stubClient();
         mockPlatformPeg();
         mockClient = mocked(MatrixClientPeg.get());
+        jest.spyOn(mockClient, "supportsExperimentalThreads").mockReturnValue(true);
 
         room = new Room(ROOM_ID, mockClient, mockClient.getUserId() ?? "", {
             pendingEventOrdering: PendingEventOrdering.Detached,