diff --git a/tests/page/page-evaluate.spec.ts b/tests/page/page-evaluate.spec.ts
index 942ef5308e..842621c8e8 100644
--- a/tests/page/page-evaluate.spec.ts
+++ b/tests/page/page-evaluate.spec.ts
@@ -550,6 +550,15 @@ it('should not use toJSON when evaluating', async ({ page }) => {
   expect(result).toEqual({ data: 'data', toJSON: {} });
 });
 
+it('should not use Array.prototype.toJSON when evaluating', async ({ page, browserName }) => {
+  it.fixme(browserName === 'firefox', 'https://github.com/microsoft/playwright/issues/6750');
+  const result = await page.evaluate(() => {
+    (Array.prototype as any).toJSON = () => 'busted';
+    return [1, 2, 3];
+  });
+  expect(result).toEqual([1,2,3]);
+});
+
 it('should not use toJSON in jsonValue', async ({ page }) => {
   const resultHandle = await page.evaluateHandle(() => ({ toJSON: () => 'string', data: 'data' }));
   expect(await resultHandle.jsonValue()).toEqual({ data: 'data', toJSON: {} });