diff --git a/extensions/matrix/src/matrix/draft-stream.test.ts b/extensions/matrix/src/matrix/draft-stream.test.ts
index 47359d09990..82eea99b725 100644
--- a/extensions/matrix/src/matrix/draft-stream.test.ts
+++ b/extensions/matrix/src/matrix/draft-stream.test.ts
@@ -180,7 +180,7 @@ function sentContentAt(callIndex: number): Record<string, unknown> {
 }
 
 function expectLogContaining(log: ReturnType<typeof vi.fn>, fragment: string): void {
-  expect(log.mock.calls.some((call) => String(call[0]).includes(fragment))).toBe(true);
+  expect(log.mock.calls.map((call) => String(call[0])).join("\n")).toContain(fragment);
 }
 
 beforeAll(async () => {
diff --git a/extensions/matrix/src/matrix/monitor/handler.group-history.test.ts b/extensions/matrix/src/matrix/monitor/handler.group-history.test.ts
index 02cb39b72be..ee576cddf4f 100644
--- a/extensions/matrix/src/matrix/monitor/handler.group-history.test.ts
+++ b/extensions/matrix/src/matrix/monitor/handler.group-history.test.ts
@@ -158,11 +158,11 @@ function finalizeInboundContextCall(
 }
 
 function expectSomeBodyContaining(bodies: readonly string[], fragment: string) {
-  expect(bodies.some((body) => body.includes(fragment))).toBe(true);
+  expect(bodies.join("\n")).toContain(fragment);
 }
 
 function expectNoBodyContaining(bodies: readonly string[], fragment: string) {
-  expect(bodies.some((body) => body.includes(fragment))).toBe(false);
+  expect(bodies.join("\n")).not.toContain(fragment);
 }
 
 describe("matrix group chat history — scenario 1: basic accumulation", () => {