diff --git a/extensions/matrix/src/matrix/client.test.ts b/extensions/matrix/src/matrix/client.test.ts
index 3b828a2e389..4bb0bbb8ad5 100644
--- a/extensions/matrix/src/matrix/client.test.ts
+++ b/extensions/matrix/src/matrix/client.test.ts
@@ -53,6 +53,13 @@ const {
 let credentialsReadModule: typeof import("./credentials-read.js") | undefined;
 let sdkModule: typeof import("./sdk.js") | undefined;
 
+function requireCredentialsReadModule(): typeof import("./credentials-read.js") {
+  if (!credentialsReadModule) {
+    throw new Error("credentials-read test module not initialized");
+  }
+  return credentialsReadModule;
+}
+
 beforeEach(() => {
   installMatrixTestRuntime();
 });
@@ -597,10 +604,11 @@ describe("resolveMatrixAuth", () => {
   });
 
   beforeEach(() => {
-    vi.mocked(credentialsReadModule.loadMatrixCredentials).mockReset();
-    vi.mocked(credentialsReadModule.loadMatrixCredentials).mockReturnValue(null);
-    vi.mocked(credentialsReadModule.credentialsMatchConfig).mockReset();
-    vi.mocked(credentialsReadModule.credentialsMatchConfig).mockReturnValue(false);
+    const readModule = requireCredentialsReadModule();
+    vi.mocked(readModule.loadMatrixCredentials).mockReset();
+    vi.mocked(readModule.loadMatrixCredentials).mockReturnValue(null);
+    vi.mocked(readModule.credentialsMatchConfig).mockReset();
+    vi.mocked(readModule.credentialsMatchConfig).mockReturnValue(false);
     saveMatrixCredentialsMock.mockReset();
     touchMatrixCredentialsMock.mockReset();
   });